题目内容：
选择题Graffiti painting is traditionally a daredevil pursuit. Teenagers dodge security guards to put their names on trains and buses. But over the past decade, graffiti has all but disappeared from Britain.s cities. Between 2007 and 2012 the number of incidents of graffiti recorded by the British Transport Police fell by 63%. A survey by the Environment Ministry shows that fewer places are blighted by tags than ever. Graffiti are increasingly confined to sanctioned walls, such as the Stockwell ball courts. In time the practice may die out entirely.
The most obvious reason for the decline in tagging and train-painting is better policing. Numerous CCTV cameras mean it is harder to get away with painting illegally. And punishments are more severe. A generational shift is apparent, too. Fewer teenagers are getting into painting walls. They prefer to play with iPads and video games. Some have gone to art school and want to make money from their paintings. The Internet means that painters can win far more attention by posting pictures online than they can by breaking into a railway yard.
Taggers and graffiti artists mostly grew up in the 1980s and 1990s. Those men—and almost all are men—are now older and less willing to take risks. Graffiti may eventually disappear. But for now the hobby is almost respectable. The former graffiti artists paint abandoned warehouses at the
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