As we all know , reading is to the mind______  food is to the body.

As we all know , reading is to the mind______  food is to the body.

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

As we all know , reading is to the mind______  food is to the body.

A. that   B. what   C. as   D. where

As we all know , reading is to the mind______  food is to the body.