Clearly, in a system ______ every decision is made on the basis of tradition alone, it may be difficult

to achieve progress.   [ ]

A. that         

B. when        

C. where     

D. which

弹性圈柱销联轴器两个半联轴器（）穿柱销的孔对准后，柱销应能自由地穿入其他各孔。

A、指定两个

B、指定一个对任意一个

C、任意一个对指定一个

D、任意两个