ITS 284 80% of Final
1) A network that runs on the customer premises is a ________. A) LAN B) WAN C) both A and B D) neither A nor B
A
1) Wireless network standards operate at ________. A) the data link layer B) the Internet layer C) both A and B D) neither A nor B
A
10) In what mode of 802.11i operation is a central authentication server used? A) 802.1X mode B) PSK mode C) both A and B D) neither A nor B
A
11) A cellular telephone uses a(n) ________. A) omnidirectional antenna B) dish antenna C) both A and B D) neither A nor B
A
11) Which of the following is a private IP address range? A) 10.x.x.x B) 128.171.x.x C) both A and B D) neither A nor B
A
12) RFC 822 and RFC 2822 standards govern ________. A) plain text content of e-mail messages B) HTTP page contents C) HTML page contents D) pages written in any language
A
13) What propagation problem is especially bad in moist air? A) absorptive attenuation B) electromagnetic interference C) multipath interference D) inverse square law attenuation
A
15) Session keys are used to ________. A) make cryptanalysis more difficult B) improve authentication C) both A and B D) neither A nor B
A
18) For 100,000 addresses, which will have fewer rows? A) a routing table B) an Ethernet switching table C) Both will be about the same length.
A
19) The highest-level DNS servers are called ________. A) root servers B) top-level servers C) both A and B D) neither A nor B
A
19) To handle multiple conversations in radio transmission, you normally use multiple ________. A) channels B) frequencies C) service bands D) wires
A
2) The Trojan horse placed on the first compromised GHOSTNET client could ________. A) conduct audio and video surveillance B) delete files C) both A and B D) neither A nor B
A
2) When a router forwards incoming packets closer to their destination hosts, this is ________. A) routing B) switching C) bridging D) relaying
A
2) Wireless LAN standards come from ________. A) OSI B) TCP/IP C) both A and B D) neither A nor B
A
2) Wireless network standards are ________ standards. A) OSI B) TCP/IP C) both A and B
A
21) In a routing table, Rows 47 and 3497 both match the destination IP address of an arriving packet's IP address. Which row will the router look at first when trying to find matches? A) 1 B) 47 C) 3497 D) the default row
A
21) The Wi-Fi Alliance calls 802.1X mode ________ mode. A) enterprise B) personal C) WEP D) WPA
A
45) Which form of Bluetooth has a typical transmission speed of less than 3 Mbps? A) classic Bluetooth B) high-speed Bluetooth C) personal Bluetooth D) none of the above
A
46) How many fields are there in an IPv6 address written for human reading? A) 8 B) 16 C) 32 D) 128
A
46) Many "T1" lines that carriers provide today use ________ in the local loop. A) 1-pair voice-grade UTP B) 2-pair voice-grade UTP C) 1-pair data-grade UTP D) 2-pair data-grade UTP
A
46) There is an access point that serves eight wireless hosts. On how many channels will these devices transmit and receive during the course of an hour or two? A) 1 B) 2 C) 8 D) 9
A
47) If I simplify the address 2001:0000:0000:00fe:0000:0000:0000:cdef, I get ________. A) 2001:::fe::::cdef B) 2001::fe::::cdef C) 2001:::fe::cdef D) 2001::00fe:::cdef
A
47) The IEEE calls 64-bit interface addresses ________. A) Extended Unique Identifiers B) Interface IDs C) MAC addresses D) half-IP
A
47) Which of the following can use access points? A) 802.11 B) Bluetooth C) both A and B D) neither A nor B
A
48) If I simplify the address 2001:0ed2:056b:00d3:000c:abcd:0bcd:0fe0, I get ________. A) 2001:ed2:56b:d3:c:abcd:bcd:fe0 B) 2001:ed2:56b:d3:c:abcd:bcd:fe C) either A or B D) neither A nor B
A
49) Dynamic ________ protocols allow routers to transmit routing table information to one another. A) routing B) transport C) synchronization D) none of the above
A
5) A company has more control over its ________ technology. A) LAN B) WAN
A
5) Users are primarily concerned with the ________ layer. A) application B) transport C) internet D) physical
A
50) A company is free to select whatever ________ dynamic routing protocol it wishes. A) interior B) exterior C) both A and B D) neither A nor B
A
50) In BitTorrent, the group of all connected computers that have all or part of the file to be downloaded is called the ________. A) swarm B) index peers C) trackers D) none of the above
A
52) In Carrier Ethernet, which service is a competitor for leased line service? A) E-Line B) E-LAN C) both A and B D) neither A nor B
A
52) The main advantage of ________ file sharing is that it brings cost savings by using clients rather than server processing power. A) BitTorrent B) client/server C) both A and B D) neither A nor B
A
52) Which of the following allows routers to check for errors in the header when a packet arrives? A) IPv4 B) IPv6 C) both A and B D) neither A nor B
A
52) ________ is an interior dynamic routing protocol. A) OSPF B) BGP C) both A and B D) neither A nor B
A
53) CSMA/CA+ACK usually is ________. A) mandatory B) optional C) not important D) efficient
A
53) Skype offers ________. A) free calling among Skype customers B) free calling to and from Public Switched Telephone Network customers C) both A and B D) neither A nor B
A
54) Which of the following is more efficient and faster? A) CSMA/CA+ACK B) RTS/CTS C) Both are about equally efficient and fast.
A
55) MPLS ________ the work that each router must do to deliver a packet during a traffic exchange. A) reduces B) increases C) does not affect D) occasionally reduces
A
55) One-bit fields are called ________ fields. A) SYN B) flag C) ACK D) none of the above
A
55) To see if a target host can be reached, you normally would send it an ICMP ________ message. A) echo request B) error advisement C) either A or B D) neither A nor B
A
55) Which of the following is the newest Wi-Fi standard? A) 802.11ac B) 802.11g C) 802.11n D) 802.11b
A
55) Which of the following uses an access point? A) traditional Wi-Fi B) Wi-Fi Direct C) both A and B D) neither A nor B
A
56) If someone says that a 1-bit flag is not set, this means that its value is ________. A) 0 B) 1 C) blank D) We cannot say.
A
56) Pinging is to send ICMP ________ messages to the target host. A) echo request B) error advisement C) ping D) echo
A
57) A TCP ________ segment is a request to close a connection. A) FIN B) ACK C) Close D) Disconnect
A
57) Wider channel bandwidth ________. A) increases transmission speed B) allows more channels to be used in a service band C) both A and B D) neither A nor B
A
58) Four-way closes use ________ segments. A) FIN B) RST C) either A or B D) neither A nor B
A
58) Which of the following steps are done in order during a call with Skype? A) login, signaling, transport B) signaling, transport, end a call C) login, signaling, end a call D) none of the above
A
59) MPLS is ________ the source and destination hosts. A) transparent to B) nontransparent to C) apparent to D) a burden on
A
6) Compared to wired transmission, propagation problems in radio transmission are ________. A) worse B) about as bad C) better
A
6) In 802.11i, protection is provided between the client and the ________. A) access point B) switch C) router D) server
A
60) Tor was created to improve ________. A) anonymity B) end-to-end encryption C) file download speed D) all of the above
A
61) WAN optimization devices are deployed ________. A) at the ends of leased lines B) by the telephone carrier C) by the PSDN carrier D) by the ISP
A
61) Which of the following can handle an application message that is one megabyte in size? A) TCP B) UDP C) both A and B D) neither A nor B
A
62) MIMO ________. A) increases throughput B) lowers propagation distance C) both A and B D) neither A nor B
A
63) In caching, ________. A) a message may not have to be transmitted B) messages are cached at the transmitting end of the line C) both A and B D) neither A nor B
A
68) Control functions are located in routers in ________. A) traditional routing B) SDN C) both A and B D) neither A nor B
A
7) An internal router only connects different IP ________. A) subnets B) networks C) both A and B D) neither A nor B
A
7) Typically, the most common way for an attacker to get extensive privileges on a computer is to ________. A) take over an application program B) take over the operating system C) take over a computer's hardware D) privilege escalation after an initial takeover
A
70) SDN ________. A) reduces CapEx B) increases OPEx C) both A and B D) neither A nor B
A
71) In SDN, a switch receives its forwarding table rules directly from ________. A) the SDN controller B) an SDN management application C) another switch D) an SNMP manager
A
73) Communication between SDN applications and SDN controllers is governed by ________. A) northbound APIs B) southbound APIs C) both A and B D) neither A nor B
A
8) Which of the following usually offers higher speeds? A) LANs B) WANs C) Both A and B are about equal in typical speeds.
A
9) In a network mask, the 1s correspond to the ________. A) network part B) subnet part C) host part D) none of the above
A
9) NAT enhances security by ________. A) preventing sniffers from learning internal IP addresses B) encryption C) both A and B D) neither A nor B
A
9) What is the strongest security protocol for 802.11 today? A) 802.11i B) 802.11s C) 802.11X D) WPA
A
1) The attack on GHOSTNET began with ________. A) a wireless vulnerability B) a social engineering attack C) malicious mobile code D) an insider attack
B
10) The other wireless device is far away in a known direction. It would be better to use ________. A) an omnidirectional antenna B) a dish antenna C) neither A nor B
B
11) In 802.11i ________, hosts must know a shared initial key. A) 802.1X mode B) PSK mode C) both A and B D) neither A nor B
B
11) The Internet is a ________. A) LAN B) WAN C) both A and B D) neither A nor B
B
12) After authentication in 80.11i PSK mode, a wireless client communicates with the access point via a(n) ________ key. A) VPN B) session C) 802.1X D) preshared
B
12) Which of the following does the carrier NOT own? A) the network core B) customer premises equipment C) both A and B D) neither A nor B
B
14) What propagation problem becomes worse as there is a large and dense object between sender and receiver? A) multipath interference B) shadow zones or dead zones C) both A and B D) neither A nor B
B
14) Which of the following allows you to connect to the hosts of almost any corporation today? A) carrier WANs B) the Internet C) both A and B
B
14) ________ is a general naming system for the Internet. A) NAT B) DNS C) DHCP D) Dotted decimal notation
B
15) For a given volume of traffic, which are more expensive? A) switches B) routers C) Both of the above are about equally expensive.
B
15) How do WAN carriers typically get their trunk lines? A) They construct them. B) They lease them from telephone companies. C) They use wireless transmission. D) They use the Internet.
B
16) ".com" is a ________. A) root domain B) top-level domain C) second-level domain D) none of the above
B
16) Routers usually are connected in a ________ topology. A) point-to-point B) mesh C) hierarchical D) bus
B
17) ".edu" is a ________. A) root domain B) top-level domain C) second-level domain D) none of the above
B
17) There is a row for each individual Ethernet address in a(n) ________. A) Router table B) Ethernet switching table C) both A and B D) neither A nor B
B
17) Which of the following allows you to read your e-mail easily on an Internet café's computer? A) POP B) Web-enabled e-mail C) both A and B D) neither A nor B
B
18) Most corporations wish to have ________ domain names. A) top-level B) second-level C) third-level D) none of the above
B
19) A(n) ________ must find the best-matching row in its ________ table by comparing multiple row matches. A) Ethernet switch, switching B) router, routing C) both A and B D) neither A nor B
B
20) DSL residential service provides ________. A) symmetric speed B) asymmetric speed C) both A and B D) neither A nor B
B
20) If a firm has many access points, it should use ________ mode in 802.11i. A) PSK B) 802.1X C) IPsec D) PEAP
B
20) Signals in a transmission usually ________. A) travel at a single frequency B) spread over a range of frequencies C) spread over the entire frequency distribution D) spread over the entire service band
B
20) Which of the following offers more reliable antivirus protection? A) antivirus software on user PCs B) antivirus software on the mail server C) Both A and B are about equally reliable.
B
21) According to the principle of defense in depth, antivirus filtering should be done in at least ________ location(s). A) 1 B) 2 C) 3 D) 4
B
22) In SNMP, the manager communicates directly with a(n) ________. A) managed device B) agent C) object D) access point
B
22) The first step in the routing process involves ________. A) selecting the best match row B) comparing the packet's destination IP address to all rows C) comparing the packet's destination IP address to matching rows D) selecting an interface
B
22) Which of the following already runs to nearly all customer premises? A) 4-pair UTP B) 1-pair VG UTP C) 1-pair DG UTP D) none of the above
B
23) 802.1X requires security between the supplicant and the authenticator in ________. A) Ethernet B) 802.11 C) both A and B D) neither A nor B
B
23) Which of the following provides end-to-end encryption? A) SSL/TLS B) PGP C) both A and B D) neither A nor B
B
24) An unauthorized internal access point is a(n) ________ access point. A) evil twin B) rogue C) shadow D) counterfeit
B
24) In ADSL, the residential customer needs a(n) ________. A) DSLAM B) ADSL modem C) both A and B D) neither A nor B
B
24) To transmit data very rapidly, you would want a ________ channel. A) narrowband B) broadband C) single-frequency band D) none of the above
B
25) In SNMP, companies are often reluctant to use ________ commands because of security dangers. A) Get B) Set C) trap D) request
B
26) The 2.4 GHz band supports ________ possible non-overlapping 20 MHz channel(s). A) 1 B) 3 C) 7 D) 11
B
28) IPsec protects ________ layer messages. A) data link B) application C) both A and B D) neither A nor B
B
28) Which of the following is usually set up by a hacker outside the building? A) a rogue access point B) an evil twin access point C) both A and B D) neither A nor B
B
29) If a company uses 802.11i for its core security protocol, an evil twin access point will set up ________ 802.11i connection(s). A) one B) two C) four D) 16
B
29) In tunnel mode, IPsec provides protection ________. A) all the way between the two hosts B) only between the IPsec servers C) both A and B D) neither A nor B
B
3) To drive around a city looking for working access points that are unprotected is ________. A) drive-by hacking B) war driving
B
30) Spread spectrum transmission is used in WLANs for ________. A) higher transmission speed B) more reliable transmission C) greater security D) more efficient transmission
B
30) Two-way amplifiers are needed for cable ________ service. A) television B) data C) both A and B D) neither A nor B
B
30) Which of the following secures communication between the wireless computer and the server it wishes to use against evil twin attacks? A) VLANs B) VPNs C) PEAP D) 802.1X mode
B
31) WLANs normally use ________. A) licensed bands B) unlicensed bands C) both A and B D) neither A or B
B
32) Centralized access point management ________. A) increases management costs but provides better control B) reduces management costs
B
33) The main disadvantage of transport mode protection compared to tunnel mode protection in IP is ________. A) that it provides protection over only part of the route B) higher cost C) both A and B D) neither A nor B
B
34) ARP operates at ________. A) Layer 2 B) Layer 3 C) both A and B D) neither A nor B
B
34) In cellular technology, the carrier antenna and equipment to which mobile customers connect directly is called a(n) ________. A) cell B) cellsite C) MTSO D) wireline carrier
B
34) VoIP users have ________ in their phones or on their computers. A) media gateways B) codecs C) both A and B D) neither A nor B
B
35) The main version of Internet Protocol in use today is IP version ________. A) 1 B) 4 C) 5 D) 6
B
36) A wireless host sends a packet to a server on the company's wired Ethernet LAN via an access point. How many frames will be involved in this one-way transmission? A) 1 B) 2 C) 4 D) There will be one frame for each switch along the way.
B
36) For the transport layer, VoIP uses ________ for transport transmission. A) TCP B) UDP C) SIP D) IP
B
37) A router will discard a packet if the Time to Live (TTL) value in an arriving packet is ________. A) 0 B) 1 C) 254 D) 256
B
37) RTP supports ________. A) faster transmission speed B) jitter control C) both A and B D) neither A nor B
B
38) Which header comes SECOND in a VoIP transport packet? A) RTP B) UDP C) TCP D) Application
B
38) ________ have SSIDs. A) Wireless clients B) Wireless access points C) both A and B D) neither A nor B
B
39) Which has stronger security? A) SSL/TLS B) IPsec C) Both have about equal security.
B
40) If a host is to be able to communicate via IPv4 and IPv6, it is said to ________. A) be bilingual B) have a dual-stack C) be IPv6-ready D) be IP-agile
B
41) Today, it can be problematic to have only a single IPv6 stack because ________. A) a single IPv4 stack is out of date B) a single IPv6 stack could not communicate with a single IPv4 stack C) a dual stack has become a common solution D) all of the above
B
41) Which of the following is used to define webpage bodies? A) HTTP B) HTML C) both A and B D) neither A nor B
B
42) Bluetooth is for ________. A) large WLANs B) cable replacement C) both A and B D) neither A nor B
B
43) Access points in the same ESS communicate via ________. A) wireless transmission B) the distribution system C) a master access point D) routers
B
43) For human reading, IPv6 address is written in ________ notation. A) decimal B) hexadecimal C) binary D) runic
B
43) How many HTTP request-response cycles are needed to transfer a webpage containing 88 lines of text and three different images? A) 3 B) 4 C) 88 D) 91
B
43) Which of the following was created for PANs? A) 802.11 B) Bluetooth C) both A and B D) neither A nor B
B
44) If the subnet ID in an IPv6 address is 32 bits, how long is the routing prefix? A) 16 bits B) 32 bits C) 64 bits D) none of the above
B
44) T1 leased lines run at a speed of about ________. A) 250 kbps B) 1 Mbps C) 10 Mbps D) 45 Mbps
B
45) The part of an IPv6 global unicast address that designates the host is called the ________. A) host part B) interface ID C) routing prefix D) none of the above
B
45) To connect two sites at 2.8 Mbps, I would use ________. A) a T1 line B) bonded T1 lines C) a T2 line D) a T3 line
B
46) In ________ file retrieval, your computer downloads a file from a server. A) P2P B) client/server C) BitTorrent D) none of the above
B
46) In an IPv6 global unicast address, the interface ID is ________ bits long. A) 32 B) 64 C) 128 D) It varies.
B
46) Which form of Bluetooth has a typical transmission speed of about 24 Mbps? A) classic Bluetooth B) high-speed Bluetooth C) enterprise Bluetooth D) none of the above
B
47) In BitTorrent, a(n) ________ website is a site the BitTorrent client program goes to in order to get .torrent files. A) swarm B) index C) tracker D) none of the above
B
47) Which of the following DSL services tends to be symmetric in speed? A) residential B) business C) both A and B D) neither A nor B
B
48) BitTorrent's .torrent files are stored on the ________. A) swarm B) index server C) tracker D) individual peers
B
48) Which of the following DSL services usually offers QoS guarantees? A) residential B) business C) both A and B D) neither A nor B
B
49) At the beginning of a telephone call placed through a Bluetooth headset with the Hands-Free Profile, which device is initially the master? A) the Bluetooth phone B) the Bluetooth headset C) Both are simultaneously masters and slaves.
B
49) If I simplify the address 2001:0000:0000:00fe:0000:0000:abcd:13ef, I get ________. A) 2001:::fe:::abcd:13ef B) 2001::fe:::abcd:13ef C) 2001:::fe::abcd:13ef D) 2001::fe::abcd:13ef
B
5) Wireless access points typically link wireless clients to ________. A) wireless servers B) servers on the wired network C) both A and B
B
50) CSMA/CD+ACK is ________. A) unreliable B) reliable C) semireliable
B
22) When an e-mail user encrypts an outgoing messages with SSL/TLS, how far will this encryption extend? A) to the sender's e-mail server B) to the receiver's e-mail server C) to the receiver's client host D) to an application program on the receiver's client host
A
23) Row 2707 has the mask /16 and the cost metric 20. Row 4400 has the mask /14 and the cost metric 10. Which row will the router choose if both are matches? A) 2707 B) 4400 C) either A or B D) The router will choose the default row.
A
23) Which of the following would be an SNMP object? A) number of rows in routing table B) a managed switch C) both A and B D) neither A nor B
A
51) In IPv6, the payload length gives the number of octets in the ________. A) entire packet B) entire packet minus the main header C) entire packet minus the main and extension headers D) entire packet minus the extension headers
B
51) The PSDN technology that is growing rapidly today is ________. A) Frame Relay B) Carrier Ethernet C) the Internet D) No PSDN technology is growing rapidly today.
B
51) Which of the following can route non-IP packets? A) OSPF B) EIGRP C) both A and B D) neither A nor B
B
52) The 802.11 standard has two mechanisms for media access control. One of two mechanisms is mandatoryit is ________. A) MAC B) CSMA/CA+ACK C) RTS/CTS D) CSMA/CD
B
54) In MPLS, the router interface to send the packet back out will be decided ________. A) during the router's routing process B) before the packet arrives C) by a dynamic routing protocol D) none of the above
B
54) Which of the following is NOT one of the main elements of the Skype network? A) login server B) proxy server C) host node D) super node
B
55) In Skype, ________ is the process where a Skype application looks up the username and IP address of the party it wants to contact. A) login B) directory search C) transport D) signaling
B
57) In MPLS, the ________ adds the label to the packet. A) source host B) first label-switching router C) both A and B D) neither A nor B
B
57) Which element of the Skype network is in charge of transport? A) the login server B) the calling and called host nodes C) super nodes D) media gateways
B
58) MPLS routers base their decisions on a packet's ________. A) destination IP address B) label number C) both A and B D) neither A nor B
B
58) Which of the following only operates in the 5 GHz band? A) 802.11b B) 802.11ac C) 802.11g D) 802.11n
B
59) An abrupt close uses a(n) ________ segment. A) FIN B) RST C) either A or B D) neither A nor B
B
59) Which of the following is a processor-sharing application? A) BitTorrent B) SETI@home C) SIP D) Skype
B
6) The advance that made the client/server application architecture possible was ________. A) the Internet B) client processing power C) application sophistication D) input/output methods
B
60) In the 5 GHz band, how many channels can you have with 802.11ac with 80 GHz channels? A) 1 B) 6 C) 12 D) 24
B
60) Which of the following segments is not acknowledged? A) FIN B) RST C) Both of the above are acknowledged. D) Neither A nor B is acknowledged.
B
24) Row 2707 has the mask /16 and the reliability metric 20. Row 4400 has the mask /16 and the reliability metric 10. Which row will the router choose if both are matches? A) 2707 B) 4400 C) either A or B D) The router will choose the default row.
A
25) A rogue access point is created by ________. A) an employee B) an external attacker C) the IT security department D) an evil twin
A
25) For ADSL service, which of the following typically must be added to the telephone system? A) a DSLAM B) a transmission line to the customer premises C) both A and B D) neither A nor B
A
25) VoIP ________ uses the Internet Protocol for transmission. A) always B) usually C) seldom D) never
A
66) The creation of routing tables for a router is an example of ________. A) forwarding B) control C) both A and B D) neither A nor B
B
26) SNMPv1 uses ________ for authentication. A) community names B) digital certificates and digital signatures C) a different password for each manager-agent pair D) all of the above
A
26) The promise of FTTH is ________. A) higher speed B) lower cost C) both A and B D) neither A nor B
A
27) A notebook computer configured to act like a real access point is a(n) ________. A) evil twin access point B) rogue access point
A
27) Companies are moving to the 5 GHz band because there is ________ than in the 2.5 GHz band. A) more bandwidth B) less absorptive attenuation C) both A and B D) neither A nor B
A
7) Which of the following has more diversity in technologies? A) LANs B) WANs C) Both A and B are about equal in diversity of technologies.
B
7) Wireless radio transmission speed is usually measured in terms of ________. A) wavelength B) frequency C) amplitude D) wetness
B
7) ________ is the process of presenting external IP addresses that are different from internal IP addresses used within the firm. A) DNS B) NAT C) DHCP D) none of the above
B
72) A router's load-balancing process is determined by ________. A) the SDN controller B) an SDN application C) the router D) any of the above
B
74) OpenFlow can be used to standardize ________. A) northbound APIs B) southbound APIs C) both A and B D) neither A nor B
B
8) Frequency is measured in terms of ________. A) nanometers B) hertz C) microns D) microseconds
B
8) In NAT, the ________ creates new external source IP addresses and port numbers. A) router B) firewall C) source host D) destination host
B
8) Which offers stronger security? A) WPA B) 802.11i C) Both A and B offer equally strong security.
B
27) Fiber to the home service is normally created by ________. A) running optical fiber to neighborhoods B) running individual fiber cords from the nearest switching building to individual homes C) both A and B D) neither A nor B
A
37) Which of the following standards permits central management? A) IPsec B) SSL/TLS C) both A and B D) neither A nor B
A
38) Which is less expensive to implement? A) SSL/TLS B) IPsec C) Both cost about the same to implement.
A
39) To use an access point, you need to know its ________. A) SSID B) BSSID C) ESSID D) Wi-Fi ID
A
4) Breaking into WLANs from outside the premises is ________. A) drive-by hacking B) war driving
A
4) Companies use carriers for WAN transmission because ________. A) companies lack rights of way B) carriers have extremely strong security C) both A and B D) neither A nor B
A
40) Leased lines offer ________ service. A) fast B) any-to-any C) rapid-connection D) none of the above
A
40) To connect to an access point, you must know its ________. A) SSID B) EUI-48 address C) IP address D) Wi-Fi ID
A
40) Which of the following is used to retrieve Web pages? A) HTTP B) HTML C) RTP D) SQL
A
41) I wish to have a wireless LAN to serve my house. I will use ________. A) 802.11 B) Bluetooth C) either A or B
A
41) Which lines run from one customer premise to another? A) leased lines B) access lines C) both A and B D) neither A nor B
A
42) In an extended service set, each access point ________. A) must have the same SSID B) must have different SSIDs C) must have coordinated SSIDs D) none of the above
A
43) A customer's leased line to its ISP connects to the ISP's ________. A) POP B) NAP C) CSU/DSU D) interface
A
43) The routing prefix in IPv6 is like the ________ part in an IPv4 address. A) network B) subnet C) host D) both A and B
A
44) The standard for roaming among access points is ________. A) 802.11r B) 802.11s C) 802.11W D) the wireless handoff protocol
A
44) Which of the following is considered a bigger problem with traditional client/server based architectures than with peer-to-peer architectures? A) underutilized processing capacity of client PCs B) potential for essential data/services to become unavailable as a device is turned off C) both A and B D) neither A nor B
A
45) Transient client presence tends to be a problem in ________. A) P2P applications B) client/server applications C) both A and B D) neither A nor B
A
45) What happens if two nearby access points use the same channel? A) They will interfere with each other. B) They will be bonded for joint operation automatically. C) They will be bonded for joint operation automatically if they are on the same ESS. D) They will be bonded for joint operation automatically if they have the same SSID.
A
1) In the TJX breach, attackers first got into the network through ________. A) spear phishing B) an inside conspirator C) the use of weak wireless encryption D) all of the above
C
1) Router connectors are called ________. A) sockets B) plugs C) interfaces D) ports
C
10) WANs are ________. A) single networks B) internets C) either A or B D) neither A nor B
C
10) Which of the following can be used within a firm? A) private IP addresses B) public IP addresses C) both A and B D) neither A nor B
C
11) In SQL injection attacks, the attacker sends ________. A) a legitimate SQL query B) a malformed SQL query C) user input that is used in an SQL query D) an SQL query in malware that is delivered to the target computer
C
11) In the mask 255.255.255.0, how many 1s are there? A) 8 B) 16 C) 24 D) We cannot say.
C
12) Which of the following is true about NAT? A) It can enhance security. B) It presents problems for some protocols. C) both A and B D) neither A nor B
C
13) Express the mask /24 in dotted decimal notation. A) 255.0.0.0 B) 255.255.0.0 C) 255.255.255.0 D) none of the above
C
13) The domain name system ________. A) is a way to find a host's IP addresses if your computer only knows the host's host name B) is a general naming system for the Internet C) both A and B D) neither A nor B
C
13) Which of the following is a common use for carrier WANs? A) to connect corporate sites B) to connect a corporate site to the Internet C) both A and B D) neither A nor B
C
16) A traditional e-mail user retrieving messages from his or her mail server could use ________. A) IMAP standard B) POP standard C) either IMAP or POP standard D) SMTP standard
C
17) In 802.11i PSK mode, the pass phrase should be at least ________ characters long. A) 8 B) 12 C) 20 D) 128
C
18) Antivirus software checks e-mail attachments for ________. A) viruses B) Trojan horses C) both A and B D) neither A nor B
C
18) Part of WPS weakness is caused by ________. A) 802.1X mode B) WPA2 preshared key mode C) dividing the 8 digit PIN into two 4 digit halves D) IPsec
C
18) The PSTN core is organized as a ________. A) mesh B) hierarchy C) modified hierarchy D) loop
C
19) DSL offers ________. A) voice transmission B) data transmission C) both A and B D) neither A nor B
C
2) A LAN is the network that ________. A) links different sites together B) provides service within a company C) provides service within a site D) all of the above
C
2) In IP subnet planning, you need to have at least 130 subnets. How large should your subnet part be? A) 6 B) 7 C) 8 D) none of the above
C
20) The default row ________. A) always has the mask /32 B) will always match the destination IP address of an incoming packet C) both A and B D) neither A nor B
C
21) A company receives its domain name from ________. A) IETF B) its ISP C) a domain registrar D) its parents
C
21) What transmission medium do ALL DSL services use? A) one-pair data-grade UTP B) two-pair data-grade UTP C) one-pair voice-grade UTP D) all of the above
C
22) In ________, the authenticator is the ________. A) 802.1X, wireless access point B) 802.11i, switch C) 802.11i, wireless access point D) 802.1X, central authentication server
C
22) To transmit very rapidly in RADIO, you need ________. A) single-frequency transmission B) single-mode transmission C) wide bandwidth D) narrow bandwidth
C
23) Channels with wide bandwidths are called ________ channels. A) multimode B) full-duplex C) broadband D) parallel
C
23) In ADSL, the customer should have ________. A) splitters B) an ADSL modem C) both A and B D) neither A nor B
C
24) Which of the following would be an SNMP object? A) number of rows in routing table B) system uptime (since last reboot) C) both A and B D) neither A nor B
C
25) 802.11 standards are being developed to work in the ________ unlicensed band. A) 2.4 GHz B) 5 GHz C) both A and B D) neither A nor B
C
25) Deciding what interface and to what device to send the packet back out is step ________ in the routing process. A) 1 B) 2 C) 3 D) 4
C
26) After selecting a row on a routing table, a router will send packets out to the ________. A) port B) socket C) interface D) plug
C
27) SNMPv3 uses ________ for authentication. A) community names B) digital certificates and digital signatures C) a different password for each manager-agent pair D) all of the above
C
28) For their transmission medium, cable television companies primarily use ________. A) 2-pair VG UTP cabling B) 2-pair DG UTP cabling C) coaxial cable D) 4-pair UTP
C
3) Wi-Fi Standards come from the ________ Working Group. A) 802.1 B) 802.3 C) 802.11 D) 802.1X
C
30) A media gateway translates ________ transmissions. A) signaling B) transport C) both A and B D) neither A nor B
C
48) A step in creating an EUI-64 is dividing a 48-bit MAC address in half and inserting ________ in the center. A) the interface ID B) the subnet ID C) fffe D) 0000
C
48) Media access control governs transmission by ________. A) access points B) wireless hosts C) both A and B D) neither A nor B
C
49) A firm uses a PSDN. It has four sites. How many leased lines will it need? A) 0 B) 1 C) 4 D) none of the above
C
49) In BitTorrent, a(n) ________ is a server that coordinates the file transfer. A) swarm B) index C) tracker D) none of the above
C
49) In CSMA/CD+ACK, when a wireless NIC wishes to transmit, it listens for traffic. If there is traffic, it waits. When the traffic stops, it may transmit immediately. A) always true B) sometimes true C) always false
C
5) 802.11i provides ________. A) confidentiality B) message integrity C) both A and B D) neither A nor B
C
5) The total length of an IPv4 address is ________ bits. A) 8 B) 16 C) 32 D) We cannot say.
C
50) In a PSDN, customers connect to the network core at ________. A) NAPs B) public/private access points C) POPs D) DSLAMs
C
50) Which Bluetooth profile would a desktop use with a Bluetooth keyboard? A) Bluetooth input profile B) Bluetooth I/O profile C) human interface device profile D) none of the above
C
51) Near-field communication has a maximum transmission distance of about ________. A) 400 cm/200 in B) 40 cm/20 in C) 4 cm/2 in D) The devices must be physically touching.
C
51) Which of the following is a security risk associated with BitTorrent? A) danger caused by opening ports on the firewall B) danger that an employee may download an infected file that cannot be rejected by filtering C) both A and B D) neither A nor B
C
53) The encapsulating security protocol offers ________. A) confidentiality B) authentication C) both A and B D) neither A nor B
C
53) Why is Carrier Ethernet popular? A) It uses a familiar technology. B) It has attractive prices. C) both A and B D) neither A nor B
C
54) TCP messages are called ________. A) frames B) packets C) segments D) fragments
C
56) In MPLS, the packet travels along the ________. A) route B) data link C) label-switched path D) MPLS path
C
56) Which element of the Skype network is in charge of signaling? A) the login server B) host nodes C) super nodes D) media gateways
C
59) In 802.11g, channel bandwidth usually is ________. A) 20 GHz B) 40 GHz C) 20 MHz D) 40 MHz
C
6) You have a 20-bit network part and a 4-bit subnet part. How many hosts can you have per subnet? A) 14 B) 16 C) 254 D) none of the above
C
61) Tor provides confidentiality ________. A) all the way to the destination host B) up to the entry P2P node C) up to the exit P2P node D) Tor does not provide confidentiality.
C
62) WAN optimization provides ________. A) network protocol acceleration B) caching C) both A and B D) neither A nor B
C
63) Beamforming can allow an access point to ________. A) direct power to individual clients B) send signals to two different clients at the same time C) both A and B D) neither A nor B
C
64) Traffic shaping ________. A) limits the amount of some types of traffic B) does not admit some types of traffic C) both A and B D) neither A nor B
C
67) Forwarding functions are located in routers in ________. A) traditional routing B) SDN C) both A and B D) neither A nor B
C
69) SDN can ________. A) permit routing rules to be changed rapidly B) reduces router costs C) both A and B D) neither A nor B
C
7) Which 802 working group created 802.11i? A) 802.1 B) 802.3 C) 802.11 D) It was not an 802 working group. It was the Wi-Fi Alliance
C
8) A mask has ________ bits. A) 8 B) 16 C) 32 D) We cannot say.
C
8) Having all privileges on a computer is known as having ________. A) access B) omniscience C) root privileges D) mojo
C
9) LANs are ________. A) single networks B) local internets C) either A or B D) neither A nor B
C
9) Radio transmission is measured in terms of ________. A) bytes per second B) wavelength C) frequency D) bits per second
C
24) What is the almost universal standard for end-to-end encryption? A) SSL/TLS B) IPsec C) PGP D) There is no almost universal standard for end-to-end encryption.
D
26) A rogue access point ________. A) is an unauthorized internal access point B) often has very poor security C) often operates at high power D) All of the above are true.
D
26) The main promise of VoIP is to ________. A) add video B) improve voice quality C) improve reliability D) reduce cost
D
27) The router selects a row in which the next-hop router is labeled local. The router will send the packet to the ________. A) default router B) local next-hop router C) local host D) destination host
D
28) The 5 GHz band usually supports about ________ non-overlapping 20 MHz channel(s). A) 1 B) 3 C) 7 D) 12
D
29) In coaxial cable, the two conductors ________. A) run side-by-side B) are twisted around each other C) both A and B D) neither A nor B
D
32) A router must use the Address Resolution Protocol process ________. A) when a new router comes online B) when a router goes offline C) whenever it forwards an IP packet D) whenever it forwards an IP packet to a host that is not in its ARP cache
D
35) Which is the correct formula for decibels? A) 10 * P2/P1 B) 10 * (P2/P1)2 C) Log10(P2/P1) D) none of the above
D
36) An 8/1 increase in power corresponds to approximately ________ decibels. A) 3 B) 6 C) 20 D) none of the above
D
36) In IPsec, agreements about how security will be done are called ________. A) tranches B) security contracts C) service-level agreements D) security associations
D
36) Which IPv4 header field is used to specify quality of service? A) type of service B) version number C) ECN D) differentiated services control point
D
38) In an IPv4 packet, the ________ field value tells the type of message contained in the IP packet's data field. A) data B) next-hop C) next-header D) protocol
D
39) Codec data comes after the ________ header in VoIP transport frames. A) IP B) TCP C) UDP D) RTP
D
39) Which is a problem with IPv4 addresses? A) They cannot be used on wireless devices. B) They are too complex. C) Routers find it difficult to handle them. D) We have run out of them.
D
4) The network part of an IPv4 address is ________ bits long. A) 8 B) 16 C) 32 D) It is hard to say with limited information.
D
4) The way in which application layer functions are spread among computers to deliver service to users is called ________. A) distributed processing B) peer-to-peer computing C) client/server computing D) an application architecture
D
4) Your firm has an 8-bit network part. If you need at least 250 subnets, what must your subnet part size be? A) 5 B) 6 C) 7 D) 8
D
41) The main benefit of IPv6 over IPv4 is ________. A) two more bits in the IP address B) two more bytes in the IP address C) the ability to have quality-of-service guarantees D) the ability to support more possible hosts
D
42) How many HTTP request-response cycles are needed to transfer a webpage containing three graphics images? A) 1 B) 2 C) 3 D) none of the above
D
42) What is pushing IPv6 adoption now? A) pressure from ISPs B) pressure from the IETF C) pressure from ISO D) none of the above
D
47) ________ is a technique for preventing two wireless stations from transmitting at the same time and therefore interfering with each other. A) Creating extended service sets B) Roaming C) The distribution system D) Media access control
D
48) In Bluetooth, a master can have up to ________ slaves at any moment. A) 1 B) 3 C) 12 D) none of the above
D
5) Your firm has an 8-bit network part and an 8-bit subnet part. How many hosts can you have per subnet? A) 126 B) 254 C) 534 D) 65,534
D
50) The version number field in IPv6 has the value ________. A) 0001 B) 0100 C) 0101 D) 0110
D
51) In ________, when a wireless host wishes to send, it first sends a message to the wireless access point asking for permission to send. When the access point sends back a response, the host sending the original message may transmit. All other hosts must wait. A) CSMA/CA+ACK B) CSMA/CA C) CSMA/CD D) RTS/CTS
D
52) In which frequency band does NFC operate? A) 2.4 GHz B) 5 GHz C) both A and B D) neither A nor B
D
53) Passive RFID chips are powered by ________. A) a battery B) the sun C) body temperature D) none of the above
D
53) ________ is used for supervisory messages at the internet layer. A) TCP B) DNS C) DHCP D) ICMP
D
54) IP is reliable because of ________. A) echo and echo reply messages B) error advisement messages C) both A and B D) neither A nor B
D
54) Passive RFID chips are powered by ________. A) a battery B) the sun C) body temperature D) the scanning unit
D
56) Today, Wi-Fi sales are dominated by ________. A) 802.11a B) 802.11g C) 802.11n D) 802.11ac
D
6) In the IPv4 address 1.2.3.4, what is the network part? A) 1 B) 1.2 C) 1.2.3 D) It is hard to say with limited information.
D
6) LAN speeds are faster than WAN speeds. This is because of ________. A) technological limitations B) regulatory limitations C) slow corporate adoption of newer WAN technologies D) economic reasons
D
60) Label-switching routers bring ________. A) lower cost B) the ability to do traffic engineering C) quality of service D) all of the above
D
61) MIMO ________. A) bonds two or more channels for higher speed B) is used in all forms of 802.11 C) uses a single spatial stream but multiple signals D) transmits multiple signals in the same channel
D
65) The highest layer in SDN consists of ________. A) switches B) routers C) the SDN controller D) SDN applications
D
9) In XSS, the malicious script that gets placed in a webpage sent to a target is ________. A) created by a Trojan horse B) sent by someone who has compromised the webserver C) embedded in a database the user queries D) sent by a user
D Explanation: D) The explosion in mobile apps makes vetting applications very difficult.
An attacker must break through two firewalls to get to a host. This illustrates the principle called ____.(select the most specific answer) A. Comprehensive security B. Risk assurance C. having a DMZ D. Defense in depth
D. Defense in depth.
In SDN, which device manages the control function for individual devices? A. SNMP manager console B. forwarding device itself C. SDN policy server D. SDN controller
D. SDN Controller
19) If companies place antivirus software on all of their client PCs, this will stop almost all virus infections.
FALSE
28) According to the IETF standards, if a router receives a series of packets from the same IP address to the same IP address, it should ________. A) go through the entire process for each packet B) cache the decision made for the first packet and use this decision on subsequent packets C) skip the first step in the routing process but go through other steps for each subsequent packet D) none of the above
A
28) Speech codecs ________. A) translate human voice signals into digital signals for transmission B) translate human voice signals into analog signals for transmission C) both A and B D) neither A nor B
A
29) Compared to normal routing, decision caching is ________. A) faster B) less dangerous C) both A and B
A
29) Spread spectrum transmission is used in WLANs because ________. A) it is required by regulators B) it offers strong security C) both A and B D) neither A nor B
A
3) A WAN is the network that ________. A) links different sites together B) provides service within about a mile C) provides service within a site D) all of the above
A
3) If you have a subnet part of 7 bits, how many subnets can you have? A) 126 B) 254 C) 510 D) none of the above
A
3) Which of the following is one of the three parts of an IPv4 address? A) subnet part B) mask C) both A and B D) neither A nor B
A
30) IPsec provides protection in two modes of operation one of these two modes is ________. A) transport mode B) data link mode C) network mode D) 802.1X mode
A
31) Compared to ADSL service, cable modem service typically is ________. A) faster and more expensive B) faster and less expensive C) slower and more expensive D) slower and less expensive
A
31) SIP is a ________ protocol for VoIP. A) signaling B) transport C) both A and B D) neither A nor B
A
31) The main limit of IPsec tunnel mode protection compared to transport mode protection in IPsec is ________. A) protection over only part of the route B) higher cost C) both A and B D) neither A nor B
A
31) What does a router do with Address Resolution Protocol request messages? A) It broadcasts them. B) It sends them directly to the destination host. C) It sends them to a next-hop router. D) It sends them to the default next-hop router.
A
32) In unlicensed bands, ________. A) you can use radios wherever you please B) you can prevent nearby businesses from setting up access points in the same channel C) both A and B D) neither A nor B
A
32) Which mode of IPsec may be more expensive if a company has a large number of computers? A) transport mode B) tunnel mode C) Both A and B are equally expensive.
A
32) Which of the following signaling standards is likely to dominate in VoIP? A) SIP B) H.323
A
33) In cellular technology, a ________ is a small geographical area. A) cell B) cellsite C) both A and B D) neither A nor B
A
34) Client PCs must have digital certificates in ________. A) transport mode B) tunnel mode C) both A and B D) neither A nor B
A
35) Access points take ________ from wireless devices and send them on to devices on the wired LAN. They also do the converse. A) packets B) frames C) both A and B D) neither A nor B
A
36) Cells are used in cellular telephony to provide ________. A) service for more customers B) greater reliability C) greater transmission speed D) all of the above
A
37) A single access point and the set of hosts it serves is called a(n) ________. A) BSS B) BSSID C) ESS D) none of the above
A
37) Today's dominant cellular technology is ________. A) LTE B) 3G C) HSPA+ D) MTSO
A
30) To deliver an arriving packet to a destination host on a subnet connected to a router, the router needs to know the destination host's ________ before the router can send the packet on to the destination host. A) IP address B) data link layer address C) both A and B D) neither A nor B
C
31) In VPNs designed to frustrate evil twin attacks, the shared secret ________. A) is transmitted in the clear B) is transmitted with cryptographic protections C) is not transmitted D) Any of the above.
C
32) Which of the following is moving toward FTTH? A) cable modem service companies B) ADSL service companies C) both A and B D) neither A nor B
C
33) A channel has more bandwidth than is necessary given data transmission speeds requirements in ________ transmission. A) normal radio B) reliable commercial C) spread spectrum D) licensed
C
33) Address Resolution Protocol is used to find the destination data link layer destination addresses of ________. A) destination hosts B) routers C) both A and B D) neither A nor B
C
33) Managed access points should ________. A) allow access point power to be adjusted remotely B) provide constant transmission quality monitoring C) both A and B D) neither A nor B
C
33) The SIP invite is transmitted to the ________. A) called party's SIP proxy server B) called party's VoIP phone or computer C) both A and B D) neither A nor B
C
34) Managed access points should ________. A) identify rogue access points B) be able to push updates out to access points C) both A and B D) neither A nor B
C
34) Which of the following uses OFDM? A) 802.11ac B) 802.11n C) both A and B D) neither A nor B
C
35) An MTSO ________. A) controls cellsites in a cellular system B) links mobile users to wired telephone customers C) both A and B D) neither A nor B
C
35) IPsec is used for ________ VPNs. A) remote-access B) site-to-site C) both A and B D) neither A nor B
C
35) Speech codecs vary with respect to ________. A) compression B) voice quality C) both A and B D) neither A nor B
C
37) A power ratio of 8/1 decrease in power corresponds to approximately ________ decibels. A) 3 B) 6 C) 9 D) none of the above
C
38) A 100/1 increase in power corresponds to approximately ________ decibels. A) 6 B) 10 C) 20 D) none of the above
C
38) What speed does the LTE Advanced standard require downstream? A) 3 Mbps B) 30 Mbps C) 3 Gbps D) 30 Gbps
C
39) 1 Watt represents a dBm value of about ________. A) 10 B) 20 C) 30 D) We cannot say because only one power is given.
C
39) Which of the following affects what throughput an individual user will receive? A) being in a moving car B) being far from the cellsite C) both A and B D) neither A nor B
C
4) We use the terms Wi-Fi and ________ interchangeably in this book. A) 802.1 B) 802.3 C) 802.11 D) 802.1X
C
40) A radio that has a power of 8 mW represents a ratio of about ________ dBm. A) 2 B) 8 C) 9 D) 10
C
40) The new version of Internet Protocol that is coming into use is IP version ________. A) 1 B) 2 C) 6 D) 8
C
41) An extended service set (ESS) is a group of BSSs that ________. A) are connected to the same distribution system B) have the same SSID C) both A and B D) neither A nor B
C
42) To use a leased line, the customer requires a(n) ________ at each site. A) switch B) router C) CSU/DSU D) modem
C
42) Which is NOT one of the three parts of a public IPv6 unicast address? A) subnet ID B) routing prefix C) host part D) All of the above are parts in a public IPv6 unicast address.
C
44) Bluetooth is standardized by the ________. A) 802.11 Working Group B) Wi-Fi Alliance C) Bluetooth Special Interest Group D) none of the above
C
44) For human reading, symbols in IPv6 addresses are written in fields of ________ symbols. A) 1 B) 2 C) 4 D) 16
C
45) For human reading, IPv6 fields are separated by ________. A) dashes B) slashes C) colons D) none of the above
C
1) If your subnet part is 8 bits long, you can have ________ subnets. A) 64 B) 128 C) 256 D) 254
D
10) A lesson of XSS is that programmers should never trust ________. A) contractors B) their own staff colleagues C) databases D) user input
D
10) In a subnet mask, the 1s correspond to the ________. A) network part B) subnet part C) host part D) none of the above
D
12) At 10 meters, a signal has a strength of 100 mW. About how strong will it be at 40 meters? A) about 0.5 mW B) about 5 mW C) about 25 mW D) about 6 mW
D
12) In the mask /14, how many 1s are there? A) 8 B) 16 C) 24 D) none of the above
D
13) After two wireless clients authenticate themselves via PSK to an access point, they will use ________ to communicate with the access point. A) the preshared key B) an 802.1X key C) WPS keys D) different session keys
D
13) E-mail bodies that have non-English text use ________. A) RFC 822 and RFC 2822 B) HTTP C) MIME D) UNICODE
D
14) A traditional e-mail user sending messages to his or her mail server would most likely use ________. A) IMAP standard B) POP standard C) either IMAP or POP standard D) SMTP standard
D
14) Express the mask /18 in dotted decimal notation. A) 255.0.0.0 B) 255.255.0.0 C) 255.255.255.0 D) none of the above
D
14) For post-authentication communication with an access point, the client in 802.11i PSK mode will ________ for subsequent communication. A) always use the same preshared key each time it is connected B) always use the same session key each time it is connected C) both A and B D) neither A nor B
D
15) In DNS, a group of resources under the control of an organization is called a ________. A) network B) subnet C) scope D) domain
D
15) Mail servers communicate with each other by using ________. A) POP B) HTTP C) RFC 2822 D) SMTP
D
15) The most serious problem with wireless transmission in WLANs is ________. A) inverse square law attenuation B) absorptive attenuation C) shadow zones D) multipath interference
D
16) In the telephone system, the lines that connect customers to the nearest switch are called the ________. A) access lines B) local lines C) access loop D) local loop
D
16) What propagation problem becomes worse as frequency increases? A) inverse square law attenuation B) electromagnetic interference C) both A and B D) neither A nor B
D
16) Which of the following is a risk in 802.11i PSK mode? A) WPS can easily be cracked if it is used. B) Unauthorized sharing of the pre-shared key. C) A weak passphrase may be selected. D) all of the above
D
17) Most end-office switches are Class ________ switches. A) 1 B) 2 C) 3 D) 5
D
17) The frequency spectrum extends ________. A) into the gigahertz range B) into the visible light range C) into the ultraviolet range D) to infinity
D
18) 2.4 GHz and 5 GHz are ________. A) frequency spectrums B) broadbands C) channels D) service bands
D
19) Which of the following has a dangerous vulnerability that is causing problems today? A) PEAP B) 802.11i C) WPA D) WPS
D
20) How many DNS root servers are there? A) 1 B) 2 C) 10 D) 13
D
21) A channel extends from 55 MHz to 60 MHz. Its bandwidth is ________. A) 60 MHz B) 55 MHz C) 65 MHz D) none of the above
D
