--Mum, we have to buy some more salt.                                      

--         .There is enough salt in our country.

A．Why not?

B．Sure.

C．I think so.

D．Don’t worry.

旅费证的各联中，（）会有一、二、三和四联的四种形式。

A.乘机联

B.换取服务联

C.出票人联

D.会计联