下列（）险种的保险费率最高。

A.定期死亡寿险

B.终身死亡寿险

C.生存保险

D.生死两全保险

A “liner” in riveted construction of a vessel is a(n) （）.

A.small plate which fills the aperture between riveted strakes and the vessel framing

B.backing plate which is used to level the strakes while riveting，and then removed

C.internal frame to which the side shell is riveted

D.seam that is welded after riveting is completed