单项选择题
A.any wire running fore-and-aft on a ship
B.any wire with a fiber core
C.a heavy wire extending from the trunk of the mast to the head of the boom
D.a heavy wire extending from the mast，atwartships to the deck，to support the mast
单项选择题 A pumproom is suspected of accumulating gases after a ventilation machinery breakdown. Where should the combustible gas indicator case be placed when testing the pumproom atmosphere for combustible gases?（）.
单项选择题 A partial deck in a hold is called a(n)（）.
单项选择题 A device used to tighten up remaining slack in wire rope when you are making up to a tow in inland waters is a（）.