精馏预处理槽的温度为（）℃。
A.130
B.150
C.200
D.250
参考答案：D
骨与关节结核的好发年龄为
A．新生儿B．婴幼儿C．儿童及青少年D．中年E．老年
_____ that he used to be a teacher. [ ]
A. It is said
B. It says
C. That is said
D. That says
