The success of her business made tough to carry out her role as wife and mother.A. thatB.

问题补充：

The success of her business made tough to carry out her role as wife and mother.

A. that

B. this

C. it

D. her

答案：

A. that

B. this

(答案→)C. it

D. her

解析：it此处用作形式宾语，代替不定式短语to carry out…。