—Can I borrow your ruler?
—Sorry, I left ___ at home. But you can buy ____ in the shop

1. A.
   it; one
2. B.
   it; it
3. C.
   one; it
4. D.
   one; one

1 

 –Can I borrow your ruler?

 ---Sorry, I left ___ at home. But you can buy ____ in the shop.

A. it; one  B. it; it  C, one; it  D. one; one