要纠正以下操作错误，需要补充其他仪器的一项是  

A．加入锌粒

B．滴加液体

C．压紧胶塞

D．加热液体

So desperate _______ that no one could help another, each ________ to save himself and his animals.

A．was the situation; was trying

B．the situation was; trying

C．was the situation; trying

D．the situation was; was trying