— Where did you find the professor who made the speech yesterday?— It was in the hall the

问题补充：

— Where did you find the professor who made the speech yesterday?

— It was in the hall the students often have a meeting.

A. where

B. which

C. that

D. when

答案：

(答案→)A. where

B. which

C. that

D. when

解析：句意：——你在那里找到了昨天做演讲的那位教授？——正是在学生们经常开会的礼堂里。先行词the hall后面的一个定语从句中不缺少主语，宾语和表语，故用关系副词where做地点状语。故选A。