It is predicted that there will be four scientific breakthroughs in the 21st century. We’ll know where we came from. Why doe

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问题     It is predicted that there will be four scientific breakthroughs in the 21st century.
    We’ll know where we came from. Why does the universe exist? To put it another way, why is there something instead of nothing? Since the 1920s, scientists have known the universe is expanding, which means it must have started at a definite time in the past. They even have developed theories that give a detailed picture of the evolution of the universe from the time it was a fraction of a second old to the present. Over the next couple of decades, these theories will be refined by data from extraordinary powerful new telescope.
    We’ll crack the genetic code and conquer cancer. In 19th century operas, when the heroine coughs in the first act, the audience knows she will die of tuberculosis in Act 3. But thanks to 20th-century antibiotics, the once-dreaded, once-incurable disease now can mean nothing more serious than taking some pills. As scientists learn more about the genetic code and the way cells work at the molecular level, many serious diseases—cancer, for one—will become less threatening. Using manufactured "therapeutic" viruses, doctors will be able to replace cancer-causing damaged DNA with healthy genes, probably administered by a pill or injection.
    We’ll live longer(120 years?). If the normal aging process is basically a furious, invisible contest in our cells—a contest between damage to our DNA and our cells’ ability to repair that damage—then 21st-century strides in genetic medicine may let us control and even reverse the process. But before we push scientists to do more, consider: Do we really want to live in a world where no one grows old and few children are born because the planet can hold only so many people? Where would new ideas come from? What would we do with all that extra time?
    We’ll have a brain road map. This is the real final frontier of the 21st century: The brain is the most complex system we know. It contains about 100 billion neurons, each connected to as many as 1,000 others. In the 21st century, we will use advanced forms of magnetic resonance imaging to produce detailed maps of the neurons in operation. We’ll be able to say with certainty which ones are working when you read a word, when you say a word, when you think about a word, and so on.
From the second paragraph, we learn that the theory about the universe starting at a definite time is based on the evidence that

选项 A、there is something instead of nothing in the universe.
B、the evolution of the universe can be pictured in detail.
C、the universe is enlarging.
D、the data from new telescope refine the theories.

答案C

解析 我们从第二段中可知,有关宇宙形成于某一特定时期的理论是基于下列哪项根据的?[A]宇宙中有物质存在而不是空无一物。[B]宇宙的演变可以详尽地描绘出来。[C]宇宙正在扩张。[D]新型望远镜所带来的数据使这些理论更加精确。根据题干中的关键词universe starting at a definite time可知相关信息出现在第二段。原文提到,自20世纪20年代以来,科学家已经了解到宇宙正在扩张。这就是说宇宙一定是在过去的某一特定时期开始形成的。which代表前半个分句theuniverse is expanding,所以[C]正确。[A]、[B]、[D]都是第二段中的内容,但是它们与题干所问的问题没有关系,是所答非所问式的干扰项。
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