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.
The passage implies that______.

选项 A、the fever process is widespread because moderate fevers have benefits
B、the reduction of fevers can inhibit bacterial growth
C、man can use sun lamp to raise lizards’ temperature
D、crayfish injected with bacteria have a purpose for moving to hot areas

答案D

解析 从文中第二段“Crayfish injected…to hot areas.”可知D 正确。
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