--- Does Ted tell you if he _______________ next Sunday?

--- No, he does’t. But if he ________________, I’ll give you a ring.

A．will come, will come

B．comes, will come

C．will come,comes

D．comes, comes

假定在某一产量水平上，某厂商的平均成本达到了最小值，这意味着( )。

A．厂商的超额利润为零
B．厂商获得了最大利润
C．边际成本等于平均成本
D．该厂商面临着一个完全竞争市场