从装有5只红球、5只白球的袋中任意取出3只球，有事件：①“取出2只红球和1只白球”与“取出1只红球和2只白球”； ②“取出2只红球和1只白球”与“取出3只红球”； ③“取出3只红球”与“取出3只球中至少1只白球”； ④“取出3只红球”与“取出3只白球”．其中是对立事件的有（ ）
A．①②
B．②③
C．③④
D．③
装有5只红球、5只白球的袋中任意取出3只球；
①“取出2只红球和1只白球”与“取出1只红球和2只白球”，可以同时发生，不是互斥事件，故①错误；
②“取出2只红球和1只白球”与“取出3只红球”；，可以同时发生，不是互斥事件，故②错误；
③“取出3只红球”还剩2只红球，5只白球，再取3只球，肯定会有一只白球，所以取出3只球中至少1只白球，与其是对立事件，不可能同时发生，
故③正确；
④“取出3只红球”与“取出3只白球，可以同时发生，不是互斥事件，故④错误；
故选D；
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