－Are you firmly against Japan’s decision to purchase the Diaoyu Islands?

－Of course. That is _______ our basic interest lies.

A．why

B．when

C．where

D．what

当有毒物品或贵重物资受到火势威胁时，应采取()的战斗方法。

（A）逐片消灭 

（B）上下合击 

（C）重点突破 

（D）内外合击