the professor paused as if ------his students to ask questions on the point he had just made.

问题描述:

the professor paused as if ------his students to ask questions on the point he had just made.
a,expecting b,to have expected c,expeted

as if 后面能接 had done / did / were /woulld do
所以选C
H意思是 老师听了一下 好像是希望学生对刚才讲的提出问题