下列钢材中，不宜用作预应力钢筋的是（）。

A.热处理钢筋

B.热轧钢筋

C.钢丝

D.钢绞线

He had __________ little education that he couldn’t teach __________ little children.

A．such; so

B．so; such

C．such; such

D．so; so