— What do you think of electric cars?

— They work well, _____ they are slow and can't run for long.

[      ]

A. and

B. but

C. or

( )阶段把逻辑解读的结果，通过输出部件输出给现场的受控元件。

A．输出采样

B．输入采样

C．程序执行

D．输出刷新