I often watch CCTV-9, ________ I have learned a lot of new words and expressions.

1. A.
   from which
2. B.
   of which
3. C.
   to which
4. D.
   which

 I often watch CCTV-9, ________ I have learned a lot of new words and expressions.

A. from which          B. of which               C. to which                     D. which

I often watch CCTV-9, ________ I have learned a lot of new words and expressions.

A. from which               B. of which           C. to which                D. which

I often watch CCTV-9, ________ I have learned a lot of new words and expressions.