－Who’s that?－A. He is my brother.B. That’s my brother.C. It’s my sister.D. She’s my sister

问题补充：

－Who’s that?

－

A. He is my brother.

B. That’s my brother.

C. It’s my sister.

D. She’s my sister.

答案：

A. He is my brother.

B. That’s my brother.

(答案→)C. It’s my sister.

D. She’s my sister.

解析：句意：—那是谁？—她是我的妹妹。当上句用that作主语时，下文不能用that来回答。本题考查交际用语中的习惯用法，故选C.