— Listen, there is some strange noise.This machine must be________.

— I think so.You must have it checked. [      ]

A. out of order  

B. out of date

C. out of sight  

D. out of control

肾活检石蜡包埋切片常用的固定液有（）

A.缓冲甲醛

B.80％乙醇

C.戊二醛

D.多聚甲醛

E.无水乙醇