We visited the school that lies in ________ was a big factory more than twenty years ago．

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

We visited the school that lies in _________was a big factory more than twenty years ago.

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

We visited the school that lies in ____ was a big factory more than twenty years ago.

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