烧结多孔砖与烧结空心砖和空心砌块相比的主要优点是（）
A.空隙率大
B.强度高
C.块度大
D.自重轻
参考答案：B
The purpose of a devil’s claw is to（）.
A.act as a chain stopper
B.prevent the windlass from engaging
C.prevent the chain from fouling on deck
D.control the wildcat
