阅读材料 回答题。To swim across the English Channel takes

阅读材料，回答题。
To swim across the English Channel takes at least nine hours. It’s a hard work and it makes you short of breath. To fly over the Channel takes only twenty minutes ( as long as you’re not held up at the airport), but it’s an expensive way to travel. You can travel by hovercraft if you don’t mind the noise, and that takes forty minutes. Otherwise you can go by boat, if you forget your seasickness ills. All these means of transport have their problems and the weary(不耐烦的) traveler often dreams of being able to drive to France in his own car. "Not possible", you say. Well, wait a minute. People are once again considering the idea of a Channel tunnel or bridge.
This time, the Greater London Council is looking into the possibility of building a Channel link straight to London. A bridge would cost far more than a tunnel, but you would be able to goby rail or by car on a bridge, whereas a tunnel would provide a rail link only.
Why is this idea being discussed again? Is Britain becoming more conscious of the need for links with Europe as a result of joining the EEC ( 欧共体) ? Well, perhaps. The main reason, though, is that a tunnel or bridge would reach the twenty square kilometers of London’s disused dockland(船坞地). A link from London to the continent would stimulate trade and revitalize(使...重新有活力) the port, and would make London a main trading centre in Europe. With a link over the Channel, you could buy your fish and chips in England, and be able to eat them in France while they were still warm!
As pointed out at the beginning of the passage， people used to think that air pollution __________. 查看材料
A.caused widespread damage in the countryside
B.affected the entire eastern half of the United States
C.had damaging effect on health
D.existed merely in urban and industries areas
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