When you’re learning to drive，_____ a good teacher makes a big difference.

A．have

B．having

C．and have

D．and having

XGN-10型开关柜采用的断路器（主开关），隔离开关与柜门的强制机械闭锁方式具有（）等特点

A.结构简单合理

B.结构复杂合理

C.操作方便

D.能满足五防要求