There is actually an overlapped area of（）ocean regions somewhere in Western European waters.

A.two

B.three

C.more than two

D.more than three

汽油机不正常燃烧主要有爆燃和表面点火，其中爆燃的危害性极大，可能打烂（）甚至冲裂汽缸体。

A.气门

B.连杆

C.活塞

D.连杆销