单项选择题
A.a vessel restricted in her ability to maneuver
B.a vessel not under command
C.a vessel engaged in fishing
D.a vessel constrained by her draught
单项选择题 A vessel travelling down a narrow channel，especially if the draft is nearly equal to the depth of the water，may set off the nearer side. This effect is known as（）.
单项选择题 A vessel towing astern in an operation which severely restricts the towing vessel and her tow in their ability to change course shall，when making way，exhibit（）.
单项选择题 A vessel is equipped with a single right-handed screw. With rudder amidships and calm wind，the vessel will most likely back（）.