A well in the uppermost deck of a shelter deck vessel which has only a temporary means of closing for the purpose of gaining an exemption from tonnage measurement is called a（n）（）.

A.Boom
B.Lift
C.Raise
D.Tackle

A.A short length of line used for temporarily holding another line
B.A snatch block for handling a topping lift
C.An engine order telegraph
D.The brake on a cargo winch

A.Standing rigging
B.A downhaul
C.A halyard
D.A jib