It_____ have been Tom that parked the car here, as he is the only one with a car.

A．may

B．must

C．can

D．should

电感和电容对交流电的阻碍作用的大小不但跟电感、电容本身有关，还跟交流电的频率有关，下列说法中正确的是（　　）

A．电感是通直流、阻交流，通高频、阻低频

B．电容是通直流、阻交流，通高频、阻低频

C．电感是通直流、阻交流，通低频、阻高频

D．电容是通交流、隔直流，通低频、阻高频