Albert Einstein was a great scientist(A.that B.what C.whom D.which)was considered a genious.

题目

Albert Einstein was a great scientist(A.that B.what C.whom D.which)was considered a genious.
加上选择的原因

答案

选A.that该关系代词可以指代人,引导定语从句.
B.what不是关系代词
C.whom是宾格的 关系代词,不能用作从句中的主语
D.which该关系代词不可以指代人