2. 职称英语
  3. If the population of the earth goes on increasing at its present rate, there

If the population of the earth goes on increasing at its present rate, there

游客2025-03-06  31
问题     If the population of the earth goes on increasing at its present rate, there will eventually not be enough resources left to keep our lives on the planet. By the middle of the 21st century, if present trends continue, we will have used up all the oil that drives our cars. Even if scientists develop new ways of feeding the human race, the crowded conditions on earth will make it necessary for us to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however, has recently been suggested by American scientist, Professor Carl Sagan.
    Sagan believes that before the earth’s resources are completely used up it will be possible to change the atmosphere of Venus and so create a new world almost as large as earth itself. The difficulty is that Venus is much hotter than the earth and there is only a tiny amount of water there. Sagan proposes that algae(藻类)organisms that can live in extremely hot or cold atmospheres and at the same time produce oxygen, should be bred in condition similar to those on Venus. As soon as this has been done, the algae will be placed in small rockets. Spaceship will then fly to Venus and fire the rockets into the atmosphere. In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon.
    When the algae have done their work, the atmosphere will become cooler, but before man ban set foot on Venus it will be necessary for the oxygen to produce rain. The surface of the planet will still be too hot for man to land on it but the rain will eventually fall and in a few years something like earth will be reproduced on Venus. [br] In the long run, the most insoluble problem caused by population growth on earth will probably be the lack of______.
选项 A、food
B、oil
C、space
D、resources
答案 D
解析 此题问的是从长远来看，人口增长带来的不可解决的问题将会是什么，属于细节事实题。从文章第一段的第一句话我们就知道，“如果地球上的人口按照目前的速度增长的话，将没有足够的资源来保证生命的延续”，后文也多处说明了资源短缺将是人口增长面临的最大的问题，所以正确答案选择D。A、B、C项在文中作为资源的例证，而且是资源这个大类下的分类，故不能作为答案。
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