Whose book is this ?---It Tom’s . There is his name on it .A. can’t be B. must be C.

问题补充：

--- Whose book is this ?

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

A. can’t be B. must be C. can be

答案：

解析：can’t be不可能是； must be一定是；can be可能是。句意：这是谁的书？根据下文，上面有他的名字。可知前文表示肯定的推断，故选B，它一定是汤姆的。