He speaks English ________ an American, so we all think he stays in America for many years.

A．as good as

B．worse than

C．as badly as

D．as well as

如图所示的电路中，电源电压保持不变，电路中只有一处故障，且只发生在电阻R或灯泡L处。当电键S由断开到闭合，两个电表示数均不变。则下列判断正确的是

A．若灯泡L发光，电阻R断路

B．若灯泡L发光，电阻R短路

C．若灯泡L不发光，灯泡L断路

D．若灯泡L不发光，灯泡L短路