战国中后期，秦国力量日益强大，对东方六国构成严重威胁，你认为下面哪一个战役使东方六国再也无力抵御秦军的进攻？[ ]

A．城濮之战

B．围魏救赵

C．长平之战

D．桂陵之战

Our English teacher bought us many new books. ______of them is very interesting.

A．All

B．Both

C．Every

D．Each