从题后方框中选出能填入空白处的最佳选项。

A: I need some school things.  1 

B: I’m sorry, but I have to do my homework. Could you get some for me?

A:   2  What do you want ?

B: Please buy a ruler for me.

A: Sure  3  .

B: Yes. I’d like some pencils, too.

A: How many do you want?

B:  4  .

A: A ruler and four pencils.  5 .

B: Yes. Thanks.                       

A: You’re welcome.

下图是201 3年7月10日前后，川西局部地区桥梁、道路等灾后景观。形成此现象的最主要原因是

A．自然原因

B．地质原因

C．气象原因

D．人为原因