Running a fever was once thought to be the prerogative of warm-blooded creatures, whose internal temperatures are independent of

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问题      Running a fever was once thought to be the prerogative of warm-blooded creatures, whose internal temperatures are independent of the weather. But, as Matthew Kluger reported in "The Importance of Being Feverish" January 1976, lizards can also develop fevers, even though there is no question that they are cold-blooded. They raise their temperatures by moving into the sun or, in the case of Kluger’s experiments, under a sun lamp. And it seems to do them some good. Sick lizards kept in cages at feverish temperatures fare much better than their counterparts in normal and cool environments.
     Now ,fever has spread to invertebrates(无脊椎动物). Recent studies have shown that crayfish and scorpions can develop fevers. Crayfish injected with bacteria and scorpions injected with prostaglandins (前列腺素)swam and scuttled to hot areas. Prostaglandins are hormones thought to be instrumental in the development of a fever.
     Evidence is also mounting that moderate fevers have their benefits, which might explain why the fever process is so widespread. Leukocytes, white blood cells that are active in fighting bacterial infections, are more mobile at febrile temperatures. And fevers reduce the amount of iron available to bacteria. That reduction, combined with high temperatures, has been shown to inhibit bacterial growth.
Which of the following best states the main idea of the passage?

选项 A、Cold-blooded animals can develop fevers.
B、There are benefits to developing fevers.
C、Fevers inhibit bacterial growth.
D、Lizards can develop fevers.

答案A

解析 该题是一道主旨题,考查对全文整体上的理解与把握。这篇文章是一篇科技文章,主要介绍了冷血动物也会发烧,并以蜥蜴、淡水鳖和蝎子为例简要地讲了其症状和影响。因此A 最能概括文章的主要内容。其余3个选项是文章中的部分细节,无法涵盖文章的主要内容。
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