单项选择题
A.smelling the bottom
B.squatting
C.bank suction
D.bank cushion
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 towing a barge astern would show，at the stern（）.
单项选择题 A vessel sighting a northern right whale dead ahead should（）.