On October 31, a newborn baby somewhere in the world will become the 7 billionth member of the human race. Or so says the UN—alt

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问题     On October 31, a newborn baby somewhere in the world will become the 7 billionth member of the human race. Or so says the UN—alternatively, this date could be at least a year too early. Behind the UN’s certainty may lay outdated and unreliable census data. The suspicion is that millions of births and deaths have not been counted and there is huge uncertainty about the rate at which women are giving birth. The precise "day of 7 billion" may not matter much. But the inaccuracies(不精确)make it harder to answer a more important question: is human population set to peak within the next few decades or will it carry on growing beyond that?
    Wolfgang Lutz of the Vienna Institute of Demography says the UN is "under political pressure to disregard(忽视)uncertainty and name a date" for 7 billion. But he and colleague Sergei Scherbov estimate that the world probably won’t reach 7 billion until early in 2013, though it could be as late as 2020. The director of the UN population division Hania Zlotnik defends her data but agrees that "an interval of a few months or even a year would be a reasonable range of uncertainty".
    One problem for demographers(人口统计学家)is undercounting. Even developed countries calculate their censuses miss up to 3 percent of people. Up-to-date figures have to adjust for both of this and the changes since the last census, which could be decades in the case of some African countries. So adjusting for extra people is routine. The big danger, Scherbov says, may be over-adjusting. The world has seen a dramatic decline in fertility in recent years, with the average woman now having only 2. 5 children, half as many as her grandmother 50  years ago. So there may be far fewer new arrivals than demographers assume.
Questions:
According to Scherbov, what is the result of over-adjusting the big danger?

选项

答案A dramatic decline in fertility.

解析 由题干中的Scherbov,big danger定位到第三段第五句.第四、五句的句意为,对多余的人口数目进行调整是惯例,但是Scherbov表示大的危险或许被矫枉过正了.第六句接着指出,近年来世界人口繁殖呈现戏剧化的衰落。由此可以判断大的危险被矫枉过正的结果就是人口繁殖的戏剧化衰落。
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