We were just about to turn to the highway when word came that the traffic on it were held up, ________ we decided to change the route back home．

1. A.
   in that case
2. B.
   in which case
3. C.
   in case which
4. D.
   in whose case

We were just about to turn to the highway when word came that the traffic on it were held up, ________we decided to change the route back home.

A. in that case        B. in which case            C. in case which           D. in whose case