The classroom is _______small _______hold (容纳) so many students. [ ]

A. enough, to

B. so, that

C. too, to

D. very, to

正火状态的过共析钢随含碳量增加，（）

A.硬度增加，强度增加

B.硬度增加，韧性下降

C.强度增加，塑性下降

D.强度下降，韧性增加