A fiber rope can be ruined by dampness because it may（）.

A.deck fitting used to secure mooring lines
B.casting fitted at the side of a weather deck，used as a fairlead
C.sharp block of wood used to support hygroscopic cargo
D.smoke pipe for the galley stove

A.strengthen the line
B.increase its efficiency
C.prevent hand injury by covering loose ends
D.make the line more flexible

A.is a deck fitting used to shackle gear to the deck
B.permits easy jettisoning of deck cargo in an emergency
C.prevents stress concentration in the bulwark
D.provides openings through the bulwark for mooring lines