If the bedplate was too rigid, then as the hull flexed, the （）, which secure the engine into the ship would be likely to break, and there would be a danger of the bedplate cracking.

A.in which
B.on which
C.to which
D.by which

A.there is a minor emergency
B.there is an actual emergency
C.there were a minor emergency
D.there were an actual emergency

A.If the first stand-by set failed
B.If the first stand-by set fails
C.If the first stand-by set will fail
D.If the first stand-by set doesn’t fail