请教语法GWD-24-41.

BettyY

In California, a lack of genetic variation in the Argentine ant has allowed the species to spread widely; due to their being so genetically similar to one another, the ants consider all their fellows to be a close relative and thus do not engage in the kind of fierce intercolony struggles that limits the spread of this species in its native Argentina.

A.due to their being so genetically similar to one another, the ants consider all their fellows to be a close relative and thus do not engage in the kind of fierce intercolony struggles that limits

B.due to its being so genetically similar the ant considers all its fellows to be a close relative and thus does not engage in the kind of fierce intercolony struggles that limit

C.because it is so genetically similar, the ant considers all its fellows to be close relatives and thus does not engage in the kind of fierce intercolony struggles that limits

D.because they are so genetically similar to one another, the ants consider all their fellows to be close relatives and thus do not engage in the kind of fierce intercolony struggles that limit

E.because of being so genetically similar to one another, the ants consider all their fellows to be a close relative and thus do not engage in the kind of fierce intercolony struggles that limits

答案选C我选的D，我说说为什么我觉得D对，首先划线句子前是分号，也就是说后面的句子是一个完整独立的句子，因此我用复数代词they没有问题，只要后面的主语是复数就行，其次limit应该是复数形式啊因为that引导前面的struggles是复数啊

为什么选C。。。。

zinniz

the spread of this species in its native Argentina.
这个its，可以排除所有的they啦

BettyY

多谢楼上 我总是忽略没有划线的句子

那我还有个问题，就是为什么limit要用单数，明明修饰的是that前面的struggles啊。。。还是说that也可以跳过去修饰前面的the kind of ？

zinniz

跳跃修饰kind啦，我觉得这个考点太隐蔽了，GMAT还是喜欢考指代~~