请教蓝皮书 15-16

Gas hydrates, chemical compounds of water and natural gas, are increasingly being studied for their potential to be huge reserviors of energy, possibly causing sea floor instability, and significant contributing to gloabal warming.

A. to be huge reserviors of energy, possibly causing sea floor instability, and

B. to be huge reserviors of energy, possibly causing sea floor instability, and even as

C. as huge reserviors of energy, possibly causing sea floor instability, and

D. as huge reserviors of energy,  and the possible cause of sea floor instability,

E. as huge reserviors of energy, as possible causes sea floor instability, and even as

这题是蓝皮书p157, 15-16题，我在大全里没有搜到。答案是A,我选的C,请问如何分辨用to be还是as?

谢谢！

这题考的是平行，答案应该是E，不用考虑是to be 还是 as

新东方这题可能答案给错了。

请问E中的表示平行么？

as huge reserviors
        of energy, as possible causes sea floor instability, and even as significant contributing
        to gloabal warming.

reserviors (noun), causes (noun), contributing (这个好像无法理解成为动名词吧。contributions)......

huge, possible, significant 都是形用词，平行....

另外，possible causes of sea floor instability应该要用介词吧....

E是有of的，可能楼主没打上去，

昨天发现这是GWD2--41，查了讨论贴，绝大多数人说是E,不过我还是倾向于XDF给的答案A,我认为：possibly causing sea floor instability不是并列的成分，是前面huge reserviors of energy造成的结果。

大家可以再斟酌一下！