__________of last term we ___________ over two thousand new words.[ ]

A. At the end; had learned

B. In the end; learned

C. By the end; have learned     

D. By the end; had learned

在冷藏库中，冷却间、冻结间和冷却物冷藏间的冷却设备应该采用( )。

A．墙排管
B．顶排管或搁架式排管
C．搁架式排管或平板冻结器
D．冷风机