题目

Which is the man’s favourite animal?A. B. C. 答案：【答案】A【解析】W: Tom , What animals do you like?M: I love many animals like elephants and penguins, but I like pandas best.如图所示，闭合开关S时，小电灯L1、L2都不亮。用一段导线的两端接触a、b两点时，两灯都不亮；接触b、c两点时，两灯也不亮；接触c、d两点时，两灯都亮。对此，下列判断中正确的是（　 ）A．灯L1 断路　　　　B．灯L2断路C．开关S断路　　　　D．灯L2短路