According to the regulations，what fire safety control feature is required in quick-closing shut off valves?（）

A.The aluminum will provide greater resistance to the spread of fire by conduction
B.The aluminum structure is usually attached to a steel coaming by a method that insulates the two metals
C.If the superstructure is stressed，an aluminum structure requires additional expansion joints to prevent fracture
D.The steel at the area of the aluminum-to-steel connection must be closely checked for galvanic corrosion

A.labeled empty and recharged as soon as possible
B.replaced in its proper location if weight loss is no more than 25%
C.replaced in its proper location regardless of weight
D.replaced in its proper location if weight loss is no more than 15%

A.any wire rope used for mooring
B.a fire-warp
C.a mooring line running diagonally to the keel
D.a mooring line perpendicular to the keel