Over the years, college students have stood together for what they believe in,from civil rights to anti-war policies to the more recent protests against the unequal distribution of wealth. But nowhere in history have students banned（禁止）bottled water. Until now. The bottled water ban,which started on just a few campuses,has now spread nationwide to more than 20 universities.The colleges have either completely banned the use of plastic bottles altogether, or some have taken a more limited approach with partial bans. Many people believe that producing and using bottled water wastes money and harms the environment. They say that bottled water is unnecessary because public water supplies in the U.S. are among the best in the world. Water fountains and reusable bottles with easy access（获取）to filling stations are a better choice. An organization called Ban the Bottle raises awareness about the economic and environmental costs of using plastic bottles. The group claims that eight glasses of water a day costs each person 49 cents annually,while drinking from plastic containers costs $1,400 per year. Plastic bottles contain antimony—a chemical that in low doses causes depression, but in large doses can even lead to death. The controversy over bottled or tap is not limited to the students and college administrations. The makers of bottled water see the movement as a threat.(80)They argue that plastic bottles make up a small portion of the nation's total waste.It's unfair to single out（单独挑出）their product when so many other items are packaged in plastic containers. Plus, water is a healthy choice compared to some sodas and juices that are also sold at school.   11@Which of the following is the main idea of the passage? Many universities ban or restrict the sale of bottled water. B.Many states ban or restrict the sale of bottled water. C.The bottled water industry is concerned about its decreasing sales. D.Many people are opposed to the bottled water ban.