[求助]几道语法题，后天就考了，急

1998年05月14

14.First designated in 1970, Earth Day has become an annual international event ______ concerns about environmental issues such as pollution.

(A) dedicated to raising

(B) dedicated raising

(C) dedicates to raise

(D) that dedicates to raising

答案选a,我想请问为何d不行？

dedicate固定用法用被动

2001年05月13

13. Fossils, traces of dead organisms found in the rocks of Earth’s crust, reveal _____ at the time the rocks were formed.

(A) what was like

(B) was like life

(C) what life was like

(D) life was like

答案选c,我想请问为何a不行？

那样的话就没有宾语了

2001年08月18

18. The bathyscaphe, a free-moving vessel designed for underwater exploration, consists of a Flotation compartment with a observation capsule attached underneath it.

我想请问到底是改c还是d?

选C，用an

1999年10月40

40. Collagen, a strong rubbery protein, supports the earflaps and the tip of nose in humans. 答

请问到底是改c还是d?

选C，可数名词不能单独出现

谢谢赐教