He told me that he would remember the days in Beijing University forever____ he got much help there from Professor Zhu.

1. A.
   where
2. B.
   which
3. C.
   that
4. D.
   when

He told me that he would remember the days in Beijing University forever____ he got much help there from Professor Zhu.

A. where        B. which        C. that     D. when