Salt deposits and moisture threaten to destroy the Mohenjo-Daro excavation in Pakistan, the site of an ancient civilization that flourished at the same time as the civilizations in the Nile Delta and the river valleys of the Tigris and Euphrates.
(A)that flourished at the same time as the civilizations
(B)that had flourished at the same time as had the civilizations
(C)that flourished at the same time those had
(D)flourishing at the same time as those did
(E)flourishing at the same time as those were
题目分析：就是一种文化发起的时间和另两种文化发起的时间是一样的，前后存在一个比较，A写的没明显错误，留着。B用had flourished，可是没有语境表明这个动词发生在过去的过去，不应该用过去完成时。C前面用flourished（过去时）可是后面用had引导，前后不对应，干掉。（既然是几种文化同时出现的意思，那么时态应该一致）。D和E前面都用ing，但是后面一个did一个用were，都是过去式，无法形成对应，干掉。选A
