----Why do you think he is feeling spiritless ?

----Because Staying up late makes him at his worst _______physical situation.

A．in terms of

B．in addition to

C．on account of

D．regardless of

在下列基本反应类型中，一定是氧化还原反应的是（）。

A、化合反应

B、置换反应

C、复分解反应

D、分解反应