She thought I was talking about her daughter in fact I was talking about my daughter.A.

问题补充：

She thought I was talking about her daughter, ,in fact, I was talking about my daughter.

A. whom

B. where

C. which

D. while

答案：

A. whom

B. where

C. which

(答案→)D. while

解析：句意：她认为我在谈论她的女儿而实际上我在谈论我的女儿。这里表示前后是对比关系，只有while有这种用法，而其他的词没有这种用法。