产生下列现象与向大气中排放的物质无关的是（ ）
A．闪电
B．酸雨
C．臭氧层空洞
D．温室效应
A、闪电是大气中产生的电火花，属于一种放电现象，与大气中排放的无知无关，故A正确；
B、酸雨是排放到大气中的二氧化硫、二氧化氮等物质形成的酸雨，故B错误；
C、臭氧层空洞是由于向空气中排放一些含氟的物质造成的，故C错误；
D、温室效应是二氧化碳的增多造成的，主要原因是化石燃料的燃烧造成的，故D错误．
故选A．
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 Every year on my birthday, from the time I turned twelve, a white gardenia was delivered to my house. No card came with it. Calls to the flower shop were not 1 at all. After a while I stopped trying to 2 the sender's name and just delighted in the beautiful white flower in soft pink paper. However, I never 3 imagining who the giver night be. Some of my happiest 4 were spent day dreaming about the sender. My mother encouraged these imaginings. She'd ask me if there was someone for whom I had shown special 5 . Perhaps it was the old man across the street whose mail I'd delivered during the winter. As a girl, though, I had more fun imagining that it might be a 6 I had run into. One month before my graduation, my father died. I felt so sad that I became completely 7 in my upcoming graduation dance, and I didn't 8 if I had a new dress or not. But my mother, despite her own sadness, would not let me 9 any of those things. She wanted her children not only to be lovable but to feel 10 . In truth, my mother wanted her children to see 11 much like the gardenia-lovely, strong and perfect with perhaps a bit of mystery (神秘) . My mother died ten days after I was married. I was twenty-two years old. That was the year the gardenia stopped 12 . | ||||
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