If you ____ your money ____ mine, we will have enough to buy one more set of stamps to ____our collection

1. A.
   join; in; add
2. B.
   add; to; add to
3. C.
   put; to; add up
4. D.
   add; in; add up to

 If you ____ your money ____ mine, we will have enough to buy one more set of stamps to ____our collection.

A. join; in; add       B. add; to; add to       C. put; to; add up    D. add; in; add up to