急问 GWD17-Q38

All Y chromosomes in existence today are descended from a single ancestor’s who is thought to have lived about 140,000 years ago.

A.      a single ancestor’s who is thought to have lived  

B.       a single ancestor’s who was thought to live

C.      a single ancestor whom it is thought had lived

D.      the Y chromosome of a single ancestor who is thought to have lived

E.       the Y chromosome of a single ancestor whom it was thought had lived
        

已经理解了who...成分是修饰chromosome的，但是为什么不能选A呢（正确答案D），前辈的讨论帖说A的ancestor’s指代不清，who不能修饰名词所有格,还是困惑...

大家能具体解释一下吗？

个人理解啊。。

就是a single ancestor's应该就是a single ancestor's y chromosomes后面加上who貌似怪怪的，因为who应该不能修饰chromosomes吧，就算能，一个染色体140000年前挂了，也是不对的