OG3 的一个问题

smartchen2005

3.Some bat caves, like honeybee hives, have residents that take on different duties such as defending the entrance, acting as sentinels and to sound a warning at the approach of danger, and scouting outside the cave for new food and roosting sites.
(A) acting as sentinels and to sound
(B) acting as sentinels and sounding
(C) to act as sentinels and sound
(D) to act as sentinels and to sound
(E) to act as a sentinel sounding
正确答案是B。前面有很多牛人讨论过了，大致同意acting as sentinels and sounding a warning at the approach of danger是并列的一个分句，但是个人觉得sounding a warning at the approach of danger是acting as sentinels 的一种表现，acting as sentinels 是一个概括性的描述，怎么能使用and来并列联系呢？

smartchen2005

没人理睬？！

自己顶