单项选择题
A．α1，α3线性无关B．α1，α2，α3，α4，α5线性相关C．α1，α2，α3，α5线性相关D．α1，α2，α3，α4，α5线性无关
A．Of course, try it on in the fitting room, please.B．This dress is on sale for half its regular price.C．Try it on, then. You don't need to ask.D．Sure, the fitting rooms are next to the stairs.