解析:
【试题来源】
2011年19省市联考(贵州/四川/福建/黑龙江/...
【解析】解法一:“至少有一处遇到绿灯”的对立面是“全是红灯”,所以概率为1-0.1×0.2×0.25×0.4=0.998,所以选择D。
解法二:四个路口都是绿灯的概率=0.9×0.8×0.75×0.6=0.324,三个路口遇到绿灯的概率=0.1×0.8×0.75×0.6+0.9×0.2×0.75×0.6+0.9×0.8×0.25×0.6+0.9×0.8×0.75×0.4=0.441,两个路口遇到绿灯的概率=0.1×0.2×0.75×0.6+0.1×0.8×0.25×0.6+0.1×0.8×0.75×0.4+0.9×0.2×0.25×0.6+0.9×0.2×0.75×0.4+0.9×0.8×0.25×0.4=0.208,一个路口遇到绿灯的概率=0.9×0.2×0.25×0.4+0.1×0.8×0.25×0.4+0.1×0.2×0.75×0.4+0.1×0.2×0.25×0.6=0.025,四种情况概率之和=0.324+0.441+0.208+0.025=0.998。因此,答案选择D选项。