The bus driver insisted that he _____ at a normal speed and therefore _____ for the child's death.[ ]

A. drive; not answer

B. was driving; shouldn't answer

C. should drive; shouldn't have answered

D. drove; shouldn't answer

将电气设备的金属外壳、配电装置的金属构架等外露可接近导体与接地装置相连称为（）。

A.保护接地

B.工作接地

C.防雷接地

D.直接接地