求一道英语习题解答The problem is that,__children who are given cow’s

求一道英语习题解答
The problem is that,__children who are given cow's milk from birth benefit greatly from it,whose have never drunk it by a certain age are able to tolerate it.
A.becaues B.provided C.whereas D.though
为什么不是B呢.选哪个?如何翻译

8.The problem is that,________ children who are given cow's milk from birth benefit greatly from it,those who have never drunk it by a certain age are not able to tolerate it.
A.because
B.provided
C.whereas
D.though
这是原题.
正确答案是C.
whereas连接词 conj.
1.（用以比较或对比两个事实）但是,然而,尽管
Some praise him,whereas others condemn him.
有些人赞扬他,而有些人谴责他.
翻译：问题是尽管一出生就喝牛奶的孩子受益很多,而那些在一定年龄前从没喝过的人却受不了牛奶.