--- Whose book is this ?

---It _____ Tom’s . There is his name on it .

A. can’t be     B. must be     C. can be

---Whose book is this? There is no name on it.
---Let me see. Oh, it’s          . I lost it a few days ago. 

 —Whose book is this ?   — It must belong         .

A. Diana               B. Diana’s        C. to Diana            D. to Diana’s

— Whose book is this?

—It must belong_________.

A. Diana ????????????? ????????????? B. Diana’s????????????? ????????????? C. to Diana????????????? ????????????? D. to Diana’s