______ is surprising to us is that Tom, for ______ English was once boring, can speak English fluently as though he were a native speaker.

A．What; whose

B．What; whom

C．It; whose

D．As; whom

企业定额的编制水平反映( )。

A．社会平均水平

B．社会平均先进水平

C．社会先进水平

D．企业实际水平