-----Have you heard that he was awarded the Nobel Prize in Literature last year?

---- ________. He has made a positive contribution to that field.

A．Congratulations!

B．You must be joking.

C．By no means!

D．He deserves it.

当使用国内生产总值反映一个国家的经济发展规模时，国内生产总值的计算应采用( )。

A．不变价格
B．现行价格
C．平均价格
D．预期价格