如图所示电路中,下列关于灯炮L1﹑L2、L3连接说法中不正确是 ()
A:S1﹑S 2都断开,L1﹑L3串联
B:S1﹑S2都闭合,L2﹑L3并联
C:S2断开,S1闭合,L1﹑L3串联
D:S2断开,S1闭合,只有L3能发光