As we all know the H1N1 Flu is so serious, students can’t go into the school _______ they take the temperature and get sure they don’t have a fever.

A．till

B．after

C．when

D．until

在金融宏观调控机制的构成要素中，变换中介是（）。

A.商业银行

B.中央银行

C.企业

D.居民户