An a.cswitchboard is usually_____ the corresponding d.cboard because of the higher voltage

An a.cswitchboard is usually_____ the corresponding d.cboard because of the higher voltage and lower currents and smaller bus-bars.

A.larger and heavier than

B.as much as

C.smaller and lighter than

D.more dangerous than

请帮忙给出正确答案和分析，谢谢！