Rules of the Road Exam 1 Question Bank
33 INLAND ONLY For the purpose of the Inland Navigation Rules, the term "inland waters" includes __________. A. the Great Lakes on the United States side of the International Boundary B. the water surrounding any islands of the United States C. the coastline of the United States, out to one mile offshore D. any lakes within state boundaries
Answer: A
4034 BOTH INTERNATIONAL & INLAND A vessel "restricted in her ability to maneuver" is one which __________. A. from the nature of her work is unable to maneuver as required by the rules B. through some exceptional circumstance is unable to maneuver as required by the rules C. due to adverse weather conditions is unable to maneuver as required by the rules D. has lost steering and is unable to maneuver
Answer: A
406 INTERNATIONAL ONLY For the purpose of the Rules, except where otherwise required, the term __________. A. "vessel" includes wing in ground craft B. "seaplane" includes nondisplacement craft C. "vessel engaged in fishing" includes a vessel fishing with trolling lines D. "vessel restricted in her ability to maneuver" includes fishing vessels
Answer: A
4167 BOTH INTERNATIONAL & INLAND A vessel which is "restricted in her ability to maneuver" under the Rules, is a vessel which is __________. A. mineclearing B. engaged in fishing C. at anchor D. not under command
Answer: A
4256 BOTH INTERNATIONAL & INLAND Traffic separation schemes established by the International Maritime Organization __________. A. provide inbound and outbound lanes to promote the safe flow of vessel traffic B. provide vessel reporting systems to assist in search and rescue in the event of a vessel casualty C. provide routing and vessel scheduling procedures to reduce shipping delays D. prohibit vessels carrying hazardous cargos from entering waters that are environmentally sensitive
Answer: A
4306 BOTH INTERNATIONAL & INLAND Which vessel is directed not to impede the passage of a vessel which can only navigate inside a narrow channel? A. A vessel of less than 20 meters in length B. A vessel not under command C. A vessel engaged in surveying D. All of the above
Answer: A
4334 BOTH INTERNATIONAL & INLAND In narrow channels, vessels of less than what length shall not impede the safe passage of vessels which can navigate only inside that channel? A. 20 meters B. 50 meters C. 65 meters D. 100 meters
Answer: A
4366 BOTH INTERNATIONAL & INLAND Which vessel is a "vessel restricted in her ability to maneuver" under the Rules? A. A vessel mine clearing B. A vessel engaged in fishing C. A vessel at anchor D. A vessel not under command
Answer: A
4411 BOTH INTERNATIONAL & INLAND For the purpose of the Rules, except where otherwise required, the term __________. A. "vessel" includes seaplanes B. "seaplane" includes nondisplacement craft C. "vessel engaged in fishing" includes a vessel fishing with trolling lines D. "vessel restricted in her ability to maneuver" includes fishing vessels
Answer: A
4442 BOTH INTERNATIONAL & INLAND Which vessel shall not impede the passage of a vessel which can only navigate inside a narrow channel? A. A vessel of less than 20 meters in length B. A vessel not under command C. A vessel engaged in surveying D. All of the above
Answer: A
4594 BOTH INTERNATIONAL & INLAND The Rules state that certain factors are to be taken into account when determining safe speed. Those factors include __________. A. state of wind, sea, and current, and the proximity of navigational hazards B. maximum attainable speed of your vessel C. temperature D. aids to navigation that are available
Answer: A
4685 BOTH INTERNATIONAL & INLAND What does the word "breadth" mean? A. Greatest breadth B. Molded breadth C. Breadth on the main deck D. Breadth at the load waterline
Answer: A
4826 BOTH INTERNATIONAL & INLAND According to the Navigation Rules, you may depart from the Rules when __________. A. you do so to avoid immediate danger B. no vessels are visible on radar C. you are in a close quarters situation D. out of sight of land
Answer: A
4841 BOTH INTERNATIONAL & INLAND A vessel transferring cargo while underway is classified by the Rules as a vessel __________. A. restricted in her ability to maneuver B. in special circumstances C. not under command D. constrained by her draft
Answer: A
6550 BOTH INTERNATIONAL & INLAND In a traffic separation scheme, when joining a traffic lane from the side, a vessel shall do so __________. A. at as small an angle as possible B. as nearly as practical at right angles to the general direction of traffic flow C. only in case of an emergency or to engage in fishing within the zone D. never
Answer: A
6560 BOTH INTERNATIONAL & INLAND A vessel using a traffic separation scheme is forbidden to __________. A. proceed through an inappropriate traffic lane B. engaged in fishing in the separation zone C. cross a traffic lane D. enter the separation zone, even in a emergency
Answer: A
69 INLAND ONLY For the purpose of the Inland Navigation Rules, the term "Inland Waters" includes __________. A. the Western Rivers, extending to the COLREGS demarcation line B. harbors and rivers to the outermost aids to navigation C. waters along the coast of the United States to a distance of two miles offshore D. None of the above
Answer: A
8002 INTERNATIONAL ONLY Which statement is true concerning a vessel "constrained by her draft"? A. She must be a powerdriven vessel. B. She is not under command. C. She may be a vessel being towed. D. She is hampered because of her work.
Answer: A
8054 INTERNATIONAL ONLY Which statement applies to a vessel "constrained by her draft"? A. She is severely restricted in her ability to change her course because of her draft in relation to the available depth of water. B. The term applies only to vessels in marked channels. C. She is designated as a "vessel restricted in her ability to maneuver". D. The vessel must be over 100 meters in length.
Answer: A
4819 BOTH INTERNATIONAL & INLAND Which breadth shown represents the breadth as defined in the Rules? (DIAGRAM 87) A. A B. B C. C D. D
Answer: A.
126 INLAND ONLY For the purpose of the Inland Navigation Rules, the term "Inland Waters" includes __________. A. the waters surrounding any islands of the U.S. B. the Great Lakes on the United States side of the boundary C. the coastline of the United States, out to one mile offshore D. any lakes within state boundaries
Answer: B
4058 BOTH INTERNATIONAL & INLAND Which factor is listed in the Rules as one which must be taken into account when determining safe speed? A. The construction of the vessel B. The maneuverability of the vessel C. The experience of vessel personnel D. All of the above must be taken into account.
Answer: B
407 INTERNATIONAL ONLY The word "vessel", in the Rules, includes __________. A. a barge permanently affixed to the shore B. wing in ground craft C. a drilling unit attached to the Outer Continental Shelf D. All of the above
Answer: B
4095 BOTH INTERNATIONAL & INLAND When underway in a channel, you should keep to the __________. A. middle of the channel B. starboard side of the channel C. port side of the channel D. side of the channel that has the widest turns
Answer: B
410 INLAND ONLY Under the Rules, the term "vessel" does NOT include __________. A. seaplane B. wing in ground craft C. hovercraft D. All of the above
Answer: B
4181 BOTH INTERNATIONAL & INLAND According to the Rules, which vessel is NOT "restricted in her ability to maneuver"? A. A vessel servicing a navigation marker B. A sailing vessel C. A vessel mineclearing D. A vessel dredging
Answer: B
4349 BOTH INTERNATIONAL & INLAND If a vessel is engaged in fishing according to the definitions in the Rules, it will have __________. A. gear extending from the side or stern B. gear that restricts maneuverability C. less than 50 percent trolling lines D. None of the above
Answer: B
4433 BOTH INTERNATIONAL & INLAND Which vessel is NOT to be regarded as "restricted in her ability to maneuver"? A. A vessel transferring provisions while underway B. A pushing vessel and a vessel being pushed when connected in a composite unit C. A vessel servicing a navigation mark D. A vessel launching aircraft
Answer: B
4504 BOTH INTERNATIONAL & INLAND While underway in a narrow channel, a vessel should stay __________. A. in the middle of the channel B. to the starboard side of the channel C. to the port side of the channel D. to the side of the channel that has the widest bends
Answer: B
4505 BOTH INTERNATIONAL & INLAND Vessels of less than what length may not impede the passage of other vessels which can safely navigate only within a narrow channel or fairway? A. 10 meters B. 20 meters C. 30 meters D. 40 meters
Answer: B
4568 BOTH INTERNATIONAL & INLAND Which vessel is "underway" according to the Rules? A. A vessel made fast to a single point mooring buoy B. A purse seiner hauling her nets C. A pilot vessel at anchor D. A vessel which has run aground
Answer: B
4700 BOTH INTERNATIONAL & INLAND What does the word "length" refer to? A. Length between the perpendiculars B. Length overall C. Waterline length D. Registered length
Answer: B
4835 BOTH INTERNATIONAL & INLAND The word "vessel", in the Rules, includes __________. A. a barge permanently affixed to the shore B. nondisplacement craft C. a drilling unit attached to the Outer Continental Shelf D. All of the above
Answer: B
4837 BOTH INTERNATIONAL & INLAND A vessel "restricted in her ability to maneuver" is one which __________. A. through some exceptional circumstance is unable to maneuver as required by the Rules B. from the nature of her work is unable to maneuver as required by the Rules C. due to adverse weather conditions is unable to maneuver as required by the Rules D. has lost steering and is unable to maneuver
Answer: B
4839 BOTH INTERNATIONAL & INLAND A vessel is considered to be "restricted in her ability to maneuver" under the Rules if she is __________. A. at anchor B. mineclearing C. engaged in fishing D. engaged in towing
Answer: B
4842 BOTH INTERNATIONAL & INLAND Which vessel is "underway" according to the Rules? A. A vessel made fast to a single point mooring buoy B. A vessel engaged in towing, not making way C. A pilot vessel at anchor D. A vessel which has run aground
Answer: B
4864 BOTH INTERNATIONAL & INLAND Which vessel shall NOT impede the passage of a vessel which can safely navigate only within a narrow channel or fairway? A. A vessel dredging B. A sailing vessel C. A vessel servicing an aid to navigation D. All of the above
Answer: B
5300 BOTH INTERNATIONAL & INLAND A traffic separation zone is that part of a traffic separation scheme which __________. A. is located between the scheme and the nearest land B. separates traffic proceeding in one direction from traffic proceeding in the opposite direction C. is designated as an anchorage area D. contains all the traffic moving in the same direction
Answer: B
74 INLAND ONLY Which term is NOT used in the Inland Navigation Rules? A. A vessel engaged in mineclearing operations B. A vessel constrained by her draft C. A vessel towing D. A vessel engaged in fishing
Answer: B
8101 INTERNATIONAL ONLY Which statement applies to a vessel "constrained by her draft"? A. The term only applies to vessels in narrow channels. B. She is severely restricted in her ability to change her course because of her draft in relation to the available depth and width of navigable water. C. She is designated as a "vessel restricted in her ability to maneuver". D. The vessel must be over 100 meters in length.
Answer: B
8103 INTERNATIONAL ONLY Which vessel is NOT "restricted in her ability to maneuver"? A. A vessel servicing an aid to navigation B. A vessel constrained by her draft C. A towing vessel with tow, unable to deviate from its course D. A vessel engaged in dredging
Answer: B
4054 BOTH INTERNATIONAL & INLAND A vessel is "engaged in fishing" when __________. A. her gear extends more than 100 meters from the vessel B. she is using any type of gear, other than lines C. she is using fishing apparatus which restricts her maneuverability D. she has any fishing gear on board
Answer: C
4090 BOTH INTERNATIONAL & INLAND According to the Navigation Rules, you may depart from the Rules when __________. A. no vessels are in sight visually B. no vessels are visible on radar C. you are in immediate danger D. out of sight of land
Answer: C
4153 BOTH INTERNATIONAL & INLAND A vessel transferring cargo while underway is classified by the Rules as a vessel __________. A. not under command B. in special circumstances C. restricted in her ability to maneuver D. constrained by her draft
Answer: C
4156 BOTH INTERNATIONAL & INLAND Which vessel is "underway" under the Rules of the Road? A. A vessel at anchor with the engine running B. A vessel with a line led to a tree onshore C. A vessel drifting with the engine off D. A vessel aground
Answer: C
4273 BOTH INTERNATIONAL & INLAND Which vessel is NOT classified as "restricted in her ability to maneuver"? A. A vessel picking up a navigation mark B. A vessel transferring cargo while underway C. A vessel whose anchor is fouled D. A vessel in a towing operation that restricts the ability of the vessel and her tow to change their course
Answer: C
4400 BOTH INTERNATIONAL & INLAND When action to avoid a close quarters situation is taken, a course change alone may be the most effective action provided that __________. A. it is done in a succession of small course changes B. it is NOT done too early C. it is a large course change D. the course change is to starboard
Answer: C
4465 BOTH INTERNATIONAL & INLAND Traffic separation schemes __________. A. provide routing and scheduling procedures to reduce shipping delays B. provide traffic patterns in congested areas, so that vessels can operate without having a separate lookout C. provide inbound and outbound lanes to promote the safe flow of vessel traffic D. prohibit vessels carrying hazardous cargoes from entering waters that are environmentally sensitive
Answer: C
4532 BOTH INTERNATIONAL & INLAND The term "powerdriven vessel" refers to any vessel __________. A. with propelling machinery onboard whether in use or not B. making way against the current C. with propelling machinery in use D. traveling at a speed greater than that of the current
Answer: C
4591 BOTH INTERNATIONAL & INLAND A vessel using a traffic separation scheme shall __________. A. only anchor in the separation zone B. cross a traffic lane at as small an angle as possible C. avoid anchoring in areas near the termination of the scheme D. utilize the separation zone for navigating through the scheme if she is impeding other traffic due to her slower speed
Answer: C
4622 BOTH INTERNATIONAL & INLAND The Navigation Rules state that a vessel shall be operated at a safe speed at all times so that she can be stopped within __________. A. the distance of visibility B. 1/2 the distance of visibility C. a distance appropriate to the existing circumstances and conditions D. the distance that it would require for the propeller to go from full ahead to full astern
Answer: C
4692 BOTH INTERNATIONAL & INLAND What is NOT a vessel "restricted in her ability to maneuver"? A. A vessel laying engaged in laying submarine cable B. A vessel towing with limited maneuverability due to a large unwieldy tow C. A deep-draft vessel that can only navigate in a dredged channel D. A towing vessel underway with a fuel barge alongside and taking on fuel
Answer: C
4827 BOTH INTERNATIONAL & INLAND The Rules state that vessels may depart from the requirements of the Rules when __________. A. operating in restricted visibility B. operating in a narrow channel C. necessary to avoid immediate danger D. the Master enters it in the ship's log
Answer: C
4829 BOTH INTERNATIONAL & INLAND The term "restricted visibility", when used in the Rules, refers to __________. A. situations when you can see vessels on radar that you cannot see visually B. visibility of less than half a mile C. any condition where visibility is restricted D. visibility where you cannot see shore
Answer: C
4843 BOTH INTERNATIONAL & INLAND According to the Rules, a vessels length is her __________. A. length between the perpendiculars B. length along the waterline C. length overall D. registered length
Answer: C
4844 BOTH INTERNATIONAL & INLAND What does the word "breadth" mean in the Rules? A. Breadth on the uppermost continuous deck B. Molded breadth C. Greatest breadth D. Breadth at the load waterline
Answer: C
4845 BOTH INTERNATIONAL & INLAND What represents the length of a vessel as defined by the Rules? (DIAGRAM 86) A. A B. B C. C. D. D
Answer: C
4847 BOTH INTERNATIONAL & INLAND The rules require which factor to be taken into account when determining safe speed? A. The construction of the vessel B. The experience of the vessel's crew C. The location of vessels detected by radar D. All of the above
Answer: C
5200 BOTH INTERNATIONAL & INLAND In a traffic separation scheme, when joining a traffic lane from the side, a vessel shall do so __________. A. only in case of an emergency or to engage in fishing within the zone B. as nearly as practical at right angles to the general direction of traffic flow C. at as small an angle as possible D. only to anchor within the zone
Answer: C
5400 BOTH INTERNATIONAL & INLAND A vessel using a traffic separation scheme shall NOT __________. A. cross a traffic lane B. engage in fishing the separation zone C. proceed in an inappropriate traffic lane D. enter the separation zone
Answer: C
10 INLAND ONLY Which term is NOT defined in the Inland Navigation Rules? A. Seaplane B. Restricted visibility C. Underway D. Vessel constrained by her draft
Answer: D
125 INLAND ONLY Under the Inland Navigation Rules, the term "Inland Waters" includes __________. A. any waters marked by U.S. aids to navigation B. harbors and rivers to the outermost aids to navigation C. waters along the coast of the United States to a distance of two miles offshore D. the Western Rivers, extending to the COLREGS demarcation line
Answer: D
16 INLAND ONLY For the purpose of the Inland Navigation Rules, the term "Inland Waters" includes __________. A. the Western Rivers B. the Great Lakes on the United States side of the International Boundary C. harbors and rivers shoreward of the COLREGS demarcation lines D. All of the above
Answer: D
36 INLAND ONLY Which type of vessel is NOT mentioned in the Inland Navigation Rules? A. An inconspicuous, partly submerged vessel B. A seaplane C. An air-cushion vessel D. A vessel constrained by her draft
Answer: D
4020 BOTH INTERNATIONAL & INLAND A vessel must proceed at a safe speed __________. A. in restricted visibility B. in congested waters C. during darkness D. at all times
Answer: D
4024 BOTH INTERNATIONAL & INLAND The word "vessel", in the Rules, includes __________. A. sailing ships B. nondisplacement craft C. seaplanes D. All of the above
Answer: D
405 INTERNATIONAL ONLY As defined in the Rules, the term "vessel" includes __________. A. WIG Craft B. nondisplacement draft C. barges D. All of the above
Answer: D
409 INTERNATIONAL ONLY Which vessel should NOT impede the navigation of a power-driven vessel? A. A vessel not under command B. A vessel engaged in fishing C. A sailing vessel D. A wing in ground craft when taking off or landing
Answer: D
4135 BOTH INTERNATIONAL & INLAND A vessel is being propelled both by sail and by engines. Under the Rules, the vessel is __________. A. a "special circumstance" vessel B. not covered under any category C. a sail vessel D. a power-driven vessel
Answer: D
4140 BOTH INTERNATIONAL & INLAND The rule regarding look-outs applies __________. A. in restricted visibility B. between dusk and dawn C. in heavy traffic D. All of the above
Answer: D
4195 BOTH INTERNATIONAL & INLAND All of the following vessels are "restricted in their ability to maneuver" EXCEPT a vessel __________. A. laying a pipeline B. dredging C. mineclearing D. not under command
Answer: D
4310 BOTH INTERNATIONAL & INLAND Which vessel is to be regarded as a vessel "restricted in her ability to maneuver"? A. A vessel fishing with trawls B. A vessel which has lost the use of her steering gear C. A vessel with a draft of such depth that she cannot change her course D. A vessel engaged in mineclearing
Answer: D
4314 BOTH INTERNATIONAL & INLAND In order for a vessel to be "engaged in fishing" she must be __________. A. underway B. using gear which extends more than 50 meters outboard C. using a seine of some type D. using gear which restricts her maneuverability
Answer: D
4320 BOTH INTERNATIONAL & INLAND Which vessel shall NOT impede the passage of a vessel which can safely navigate only within a narrow channel or fairway? A. A vessel of less than 20 meters in length B. A vessel sailing C. A vessel fishing D. All of the above
Answer: D
4358 BOTH INTERNATIONAL & INLAND Which vessel should not impede the navigation of a power-driven vessel? A. A vessel not under command B. A vessel engaged in fishing C. A sailing vessel D. A seaplane
Answer: D
4410 BOTH INTERNATIONAL & INLAND The rules state that vessels may depart from the requirements of the Rules when __________. A. there are no other vessels around B. operating in a narrow channel C. the Master enters it in the ship's log D. necessary to avoid immediate danger
Answer: D
4440 BOTH INTERNATIONAL & INLAND Which craft would be considered a "power-driven vessel" under the Rules of the Road? A. An auxiliary sail vessel, using her engine B. A canoe being propelled by a small outboard motor C. A tug powered by a diesel engine D. All of the above
Answer: D
4455 BOTH INTERNATIONAL & INLAND Which vessel is "underway" within the meaning of the Rules? A. A vessel at anchor with the engine turning B. A vessel tied to an offshore mooring buoy C. A vessel aground with the engine turning D. A vessel drifting with the engine stopped
Answer: D
4467 BOTH INTERNATIONAL & INLAND Under the Rules, the term "vessel" includes __________. A. non-self-propelled raft B. seaplanes C. hovercrafts D. All of the above
Answer: D
4521 BOTH INTERNATIONAL & INLAND According to the Navigation Rules, all of the following are engaged in fishing EXCEPT a vessel __________. A. setting nets B. trawling C. using a dredge net D. trolling
Answer: D
4541 BOTH INTERNATIONAL & INLAND The Rules state that vessels may depart from the Rules when __________. A. there are no other vessels around B. operating in a narrow channel C. the Master enters it in the ship's log D. necessary to avoid immediate danger
Answer: D
4577 BOTH INTERNATIONAL & INLAND Which statement about the Navigation Rules is TRUE? A. The rules require vessels to comply with Traffic Separation Scheme regulations. B. The rules use the term "safe speed." C. The Rules permit a stand-on vessel to take action prior to being in extremis. D. All of the above are correct.
Answer: D
4579 BOTH INTERNATIONAL & INLAND As defined in the Rules, the term "vessel" includes __________. A. seaplanes B. nondisplacement craft C. barges D. All of the above
Answer: D
4592 BOTH INTERNATIONAL & INLAND A proper look-out shall be maintained __________. A. only at night B. only during restricted visibility C. at night and during restricted visibility D. at all times
Answer: D
4619 BOTH INTERNATIONAL & INLAND Which vessel is NOT to impede the passage of a vessel which can only navigate safely within a narrow channel? A. Any vessel less than 20 meters in length B. Any sailing vessel C. A vessel engaged in fishing D. All of the above
Answer: D
4705 BOTH INTERNATIONAL & INLAND In complying with the Rules, of what must the mariner take due regard? A. Limited backing power of his vessel B. Radar information about nearby vessels C. The occupation of the other vessel, if known D. All of the above
Answer: D
4715 BOTH INTERNATIONAL & INLAND What is a "vessel restricted in her ability to maneuver"? A. A deep-draft vessel that can only navigate in a dredged channel B. A vessel fishing with a bottom trawl that must remain on course C. A large tanker that is being towed as a dead ship to dry dock D. A vessel laying revetment mats to provide bank protection along a channel
Answer: D
4828 BOTH INTERNATIONAL & INLAND The Rules state that vessels may depart from the Rules when __________. A. there are other vessels in the vicinity B. operating in a traffic separation scheme C. engaged in a situation involving more than two vessels D. necessary to avoid immediate danger
Answer: D
4831 BOTH INTERNATIONAL & INLAND Which craft is a "power-driven vessel" under the Rules of the Road? A. An auxiliary sailing vessel, using her engine B. A canoe propelled by a small outboard motor C. A trawler on her way to the fishing grounds D. All of the above
Answer: D
4838 BOTH INTERNATIONAL & INLAND What determines if a vessel is "restricted in her ability to maneuver"? A. Whether or not all of the vessel's control equipment is in working order B. The vessel's draft in relation to the available depth of water C. Whether the vessel is operating in a narrow channel D. The nature of the vessel's work, limiting maneuverability required by the Rules
Answer: D
4848 BOTH INTERNATIONAL & INLAND The Rules state that certain factors are to be taken into account when determining safe speed. One of the factors is the __________. A. radio communications that are available B. maximum speed of your vessel C. temperature D. current
Answer: D
6540 BOTH INTERNATIONAL & INLAND A vessel may enter a traffic separation zone __________. A. in an emergency B. to engage in fishing within the zone C. to cross the traffic separation scheme D. All of the above
Answer: D
6570 BOTH INTERNATIONAL & INLAND A traffic separation zone is that part of a traffic separation scheme which __________. A. is between the scheme and the nearest land B. contains all the traffic moving in one direction C. is designated as an anchorage area D. separates traffic proceeding in one direction from traffic proceeding in the opposite direction
Answer: D
8006 INTERNATIONAL ONLY The International Rules of the Road apply __________. A. to all waters which are not inland waters B. only to waters outside the territorial waters of the United States C. only to waters where foreign vessels travel D. upon the high seas and connecting waters navigable by seagoing vessels
Answer: D
8071 INTERNATIONAL ONLY Which vessel is NOT regarded as being "restricted in her ability to maneuver"? A. A vessel servicing an aid to navigation B. A vessel engaged in dredging C. A towing vessel with tow unable to deviate from its course D. A vessel constrained by her draft
Answer: D
8100 INTERNATIONAL ONLY The International Rules of the Road apply __________. A. to all waters B. to any waters inside the territorial waters of the U.S. C. only to waters where foreign vessels travel D. upon the high seas and connecting waters navigable by seagoing vessels
Answer: D
8102 INTERNATIONAL ONLY Which statement is TRUE concerning a vessel "constrained by her draft"? A. She is hampered because of her work. B. She is unable to maneuver due to some exceptional circumstance. C. She may be a vessel being towed. D. She must be a powerdriven vessel.
Answer: D
