单项选择题
A.The type of anchor and mooring line being used
B.The type of bottom in which the ship is anchored
C.A significant difference between air and water temperature
D.The chain contacting a chock or fairlead between the tensiometer and the lower swivel fairlead
单项选择题 We took usual steps:sounding the depth，reversing and stopping engine，paying out anchor and 60 fathoms of chain cable in the depth of 12 fathoms．The operation above is（）.
单项选择题 Wale shores would be used when drydocking a vessel with（）.
单项选择题 Vessels lying afloat at buoys for more than 24 hours should use anchor chain for（）and insurance wire for（）.