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标题: gwd求助 [打印本页]

作者: ypl214 时间: 2010-7-30 17:17
标题: gwd求助

Whales originated in the freshwater lakes and rivers of ancient Asia about sixty million years ago.Not until about ten million years later did species of whales develop specialized kidneys enabling them to drink salt water.Although fossil evidence shows that some early whale species that lacked such kidneys sometimes swam in the Earth’s saltwater oceans, these species must have had to return frequently to freshwater rivers to drink.

Which of the following is most strongly supported by the information given?

A.Fossils of whale species dating from between sixty million and fifty million years ago will not be found on continents that were at the time separated from ancient Asia by wide expanses of ocean.

B.Among whale fossils that date from later than about fifty million years ago, none are fossils of whale species that drank only fresh water.

C.Fossils of whale species that drank fresh water will not be found in close proximity to fossils of whale species that drank salt water.

D.The earliest whales that drank salt water differed from fresh-water-drinking whales only in their possession of specialized kidneys.

E.Between sixty million and fifty million years ago, the freshwater lakes and rivers in which whales originated were gradually invaded by salt water.

作者: sunli2829 时间: 2010-7-30 17:45
排除法，B,C,D,E明显错，选A.
其实对A的理解比较纠结，我刚看时完全不知所云。A表达的意思是5千万-6千万年年龄的这种鲸鱼化石不可能在被远离古亚洲的大陆找到（两大陆间被大片海洋包围），其实就是说那时的鲸鱼还不能长时间脱离淡水，它游不了那么远，因此鲸鱼的活动范围必然在亚洲大陆附近的海域或飘到亚洲大陆。如果我们追究--鲸鱼死后可能会被海水冲得很远，那就没有必要了，因为原文说了是广阔的海，更别去想什么大陆漂移理论了，这就是GMAT，没有最好只有相对好，说得通就可以了

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