It was she that a sharp whistle which makes possible for us to catch the thief.A. gave of

问题补充：

It was she that a sharp whistle, which makes possible for us to catch the thief.

A. gave off; this

B. gave out; that

C. gave; it

D. sent out; them

答案：

@@A. gave off; this@@B. gave out; that@@(答案)C. gave; it@@D. sent out; them

解析：前半句即主句是强调句，强调she；后半句是which引导的非限制生定语从句，it为形式宾语，指代真正的宾语即动词不定式短语to catch the thief.