【单选题】
C至少有1个发生的概率为()
①
<imgwidth="15"height="41"v:shapes="_x0000_i1054"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image060.png">
②
<imgwidth="15"height="41"v:shapes="_x0000_i1055"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image062.png">
③
<imgwidth="16"height="41"v:shapes="_x0000_i1056"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image064.png">
④
<imgwidth="15"height="41"v:shapes="_x0000_i1057"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image066.png">