When a vessel navigates in an area with a small underkeel clearance but with adequate space to take avoiding action she（）.

单项选择题A twin-screw vessel can clear the inboard propeller and maneuver off a pier best by holding a(n)（）.

A.forward spring line and going slow ahead on the inboard engine
B.after spring line and going slow astern on the outboard engine
C.forward spring line and going slow ahead on both engines
D.forward spring line and going slow ahead on the outboard engine

单项选择题A twin-screw vessel is easier to maneuver than a single-screw vessel because the twin-screw vessel（）.

A.permits the rudder to move faster
B.generates more power
C.can turn without using her rudder
D.can suck the water away from the rudder

单项选择题A vessel which through some exceptional circumstance is unable to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel is called（）.

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In towing，heaving lines are used for（）.

A.passing a tow bridle to the tug
B.passing a messenger line
C.heaving in the tow bridle
D.service lines with rocket line throwers

单项选择题In twin-screw engine installations while going ahead，maneuvering qualities are most effective when the tops of the propeller blades both turn（）.

A.to starboard
B.outboard from the center
C.to port
D.inboard toward the center