.Most of the problems the government had been paying much attention to __ at last.

A．solve

B．being solved

C．were solved

D．are solved

急性肾小球肾炎血清补体，一过性明显下降，恢复正常的时间是（）。

A.2～3周

B.4～5周

C.6～8周

D.9～11周

E.12～5周