He is a man of great knowledge, ___much can be learned.

1. A.
   in whom
2. B.
   about whom
3. C.
   from whom
4. D.
   of whom

He is a man of great knowledge, ___much can be learned.

A. in whom           B. about whom           C. from whom         D. of whom

He is a man of great knowledge, ____ much can be learned.
A in whom B about whom　C from whom　D of whom

He is a man of great knowledge, ________ much can be learned.

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He is a man of great knowledge, ________ much can be learned.

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