We all know Liuqian. He              his magic shows. [ ]

A. is good at

B. is weak at

C. is famous as

D. is famous for

在水准仪上，调节水准仪符合水准器的螺旋是（）。

A.脚螺旋

B.竖直微倾螺旋

C.水平微动螺旋

D.水平制动螺旋