What does the text mainly discuss?

A．Threats from the new microbes in the next century．

B．How new viruses affect the human society．

C．what megacities may bring to human species．

D．The disastrous effect of nuclear and biological weapons．

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答案解析

该题为主旨题。全文主要论述二十一世纪我们会遇到细菌入侵的问题。第一段阐述21世纪会有新型病毒出现；第二段阐述病毒侵袭人类的原因；第三段阐述为什么大城市是新型病毒青睐的对象；第四、五段阐述生化武器会在未来出现；最后一段作者展望未来，并且相信人类会战胜生化武器。选项A“下个世纪有来自新型细菌的威胁”符合文意。选项B“新型细菌怎样影响人类社会”和选项C“大城市会给人类带来什么”在文中没有提到；选项D“核武器和生化武器的灾难性影响”在文中倒数第二、三段提到过，但这只是文章内容的一部分并不能作为全文的主旨，故选A。

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1 根据下面资料，回答题
Given the fact that each person is only one of approximately 90 million voters in this country,does it make sense to believe that one person´s participation, one vote, will have any impact on a major election? Simply to raise the question "What if everyone felt the same way?" does not re-move the lingering impression that a single person is made to feel insignificant by the enormous number of people who do go to the polls, especially in a national election.
Supporters of the ruling elite theory insist that even though voters are given a choice among candidates, their choice is restricted to a narrow range of similar-minded individuals approved by the ruling elite. Elections do not express what most people want or need, nor do they provide guidance for politicians (even if they want it) on what policies to enact. In this view, elections are primarily just rituals that perform a symbolic function for society.
Still, since most people continue to show faces at the polls at one time or another, what argu-ments can be made in favor of voting? One argument is that voting does have significance, if not in individual impact, then in group pressure. Because citizens collectively have the power to give or withhold votes, they directly control the term in office of elected officials. Even if the choice is be-tween Tweedledee and Tweedledum, Tweedledee knows that one must be accountable and this is fixed by law, and that minimally he or she must strive to avoid displeasing the constituents to lose the job.
But perhaps political effectiveness and impact in voting are not the only consideration anyway.
People do not vote only to influence policy. Millions go to the effort to register and vote for a varie-ty of other reasons as well. Some people may participate just to avoid feeling guilty about not voting. They may have been taught that is their patriotic duty to vote and that they have no right to complain about the outcome if they stay at home. Still others may vote to derive satisfaction from feeling that they are somehow participants, not just spectators, in an exciting electoral contest.
Even if their one vote may not be crucial to the outcome, it nevertheless affirms their role in and support for the political process. Indeed, perhaps it is this final need that fuels the desire for full democratic participation among people in many nations of the world.
What is the true nature of elections according to the ruling elite theory?

A．They are routine practices in a modem society．

B．They are political gathering for a small number of people．

C．They are deceptive schemes manipulated by the ruling party．

D．They are chances for those who want to utter their wishes．

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2 According to Paragraph 3，people go to the polls because they

A．believe it’s their responsibility to vote．

B．believe their collective power makes a difference．

C．want to show the strength and impact of each individual．

D．don’t want to risk losing their jobs．

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3 “Tweedledee and Tweedledum”(Line 5，Paragraph 3)is used to refer to

A．two voting individuals in an election．

B．whatever parties in office．

C．whichever candidates in ail election．

D．supporters in different constituencies．

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