The concept of obtaining fresh water from icebergs that are towed to populated areas and arid regions of the world was once trea

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问题     The concept of obtaining fresh water from icebergs that are towed to populated areas and arid regions of the world was once treated as a joke more appropriate to cartoons than real life. But now it is being considered quite seriously by many nations, especially since scientists have warned that the human race will outgrow its fresh water supply faster than it runs out of food.
    Glaciers are a possible source of fresh water that has been overlooked until recently. Three-quarters of the Earth’s fresh water supply is still tied up in glacial ice, a reservoir of untapped fresh water so immense that it could sustain all the rivers of the world for 1, 000 years. Floating on the oceans every year are 7, 659 trillion metric tons of ice encased in 10, 000 icebergs that break away from the polar ice caps, more than ninety percent of them from Antarctica.
    Huge glaciers that stretch over the shallow continental shelf give birth to icebergs throughout the year. Icebergs are not like sea ice, which is formed when the sea itself freezes, rather, they are formed entirely on land, breaking off when glaciers spread over the sea. As they drift away from the polar region, icebergs sometimes move mysteriously in a direction opposite to the wind, pulled by subsurface currents. Because they melt more slowly than smaller pieces of ice, icebergs have been known to drift as far north as 35 degrees south of the equator in the Atlantic Ocean. To corral them and steer them to parts of the world where they are needed would not be too difficult.
    The difficulty arises in other technical matters, such as the prevention of rapid melting in warmer climates and the funneling of fresh water to shore in great volume. But even if the icebergs lost half of their volume in towing, the water they could provide would be far cheaper than that produced by desalinization, or removing salt from water.
With which of the following would the author be likely to agree?

选项 A、Towing icebergs to dry areas is economically possible.
B、Desalination of sea water is a promising way to obtain drinking water.
C、Using water from icebergs is only a short-term solution to water shortage.
D、Icebergs could not be towed very far before they would melt.

答案A

解析 细节判断题。原文首段首句提到了obtaining fresh water from icebergs…towed to…arid regions ofthe world信息,接着在原文首段尾句的表达是对此给予了肯定,选项A正确;由文章尾句icebergs…would be far cheaper than that produced by desalinization,or removing salt from water的信息可知,即使有损失,但从冰山获取淡水,远比从海水中脱盐取得淡水便宜,选项B不正确;选项C的内容,原文没有提及;由原文第三段倒数第二句可知,由于冰山比小块的冰融化要慢,因此有的冰山在大西洋中向北飘到了赤道以南35°的地方,选项D中的could not be towed very far与此矛盾。故答案为A。
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