—Could I speak to Miss Smith, please?

—______． She’s gone to the post office．

A．I’m afraid not

B．I think so

C．Certainly you can.

D．I’m not sure．

当前，转炉广泛采用（）技术，使转炉的炉龄有了很大的提高。

A.干法喷补

B.湿法喷补

C.溅渣护炉