Question

I really don’t know ___ ___I kept the secret papers.

A．where was it

B．it was where that

C．where it was that

D．where was it that

Answer 1

C

考察宾语从句和强调句的结合。根据句子结构可知，该句为宾语从句和强调句的结合。
宾语从句中要使用陈述语气，