根据情景，选择正确的句子。

1.想知道Mum在哪里，你可以说：____        [ ]

A. Where's he?    

B. Where's she?    

C. Where's Mum?

2.别人问你的事情如果你不知道，你可以说：   _              [ ]

A. He's in the study.    

B. Sorry, I don't know.    

C. She's in the kitchen.

3.你找不到你的小刀了，你想问别人在哪里，可以说：   _          [ ]

A. Where's he?    

B. Where's she?    

C. Where's it?

4.照相机在冰箱上，你可以说：____       [ ]

A. It's on the fridge.    

B. Sorry, I don't  know.    

C. It's in the fridge.