【正确答案】
D
【答案解析】[听力原文] Professor: I noticed on my way to class today that someone has spray-painted an image with slogans on the wall of the Student Union. Have any of you seen that yet? I guess they're just expressing their enthusiasm for the football season. It's not a very artistic effort, but it is a perfect example of the kind of modem art I want to talk about today: graffiti—humorous, political or rude writing and pictures on the walls of buildings, trains etc. Of course, graffiti is not modern at all. Actually, we could go a lot further back into prehistory for examples, to the famous cave paintings of Lascaux, for instance—but these probably don't fit the definition, since a main characteristic of graffiti is that it's drawn or written on someone else's property without permission—and consequently with some haste! Generally we can classify the graffiti into gang graffiti, socio-political graffiti, expressive or humorous graffiti, and public art. Gang graffiti appeared after World War Two, when our cities were getting much bigger, and the social stresses and strains of urban living led to the rise of urban gangs. The identifying signs and logos were painted on boundary walls and buildings to warn other gangs away. And these days, you can see a lot of political graffiti just by watching the evening news from the Middle East or other areas of conflict. On the buildings in the background you can see slogans calling for 'Liberty' or 'Free Speech' or other social changes. You can also find humorous, expressive, generally harmless graffiti in the toilet stalls of any bar or college campus. Dozens of these old jokes, along with many new and imaginative comments, decorate our public toilets—people just expressing themselves, and often in very funny ways. But for me, what encourages me most is how some of the creations of these 'writers', as they are called, some of their creations have risen to the level of art, of public art. Why does the lecturer mention the image with slogans on the wall of the Student Union? 录音一开始教授提到了学生会外墙上带有标语的图画并做简单评价，以此引入该录音的主题：涂鸦艺术(graffiti)，故答案为D。