GRE

Thediscovery of subsurface life on Earth, surviving independently from surfacelife, refuted the belief that biological processes require not only liquidwater but sunlight as well, thus greatly enhancing the possibility of lifebeyond Earth. Take Jupiter’s moonEuropa. Space probes show a body covered with a thick layer of ice. AsEuropa orbits its planet, however, it flexes due to the gravitationaltug-of-war between it, its sister moons, and Jupiter. Through friction, thisflexing produces heat in the moon’s interior capable of melting ice. Indeed,observations suggest liquid water exists beneath Europa’s icy crust.Photosynthetic life is impossible there because sunlight is completely absent,but life such as the microbes that flourish deep within earth may still bepossible.

The highlighted sentence “take Jupiter’s moon Europa” serves tointroduce

A. aninstance that allows a hypothesis to be tested

B. speculationgrounded in empirical discovery

C. a deductionfrom a newly advanced hypothesis

D. alarge-scale effect of an apparently insignificant contingency

E. thederivation of a contradiction to refute a claim

解析

阅读思考呀!注意段落结构和作者思路呀!

答案：B

解析：为什么是B不是A呢?为什么呢?为什么呢?

要看文章结构呀!文章首先说地球上的一个重要发现，接着说该发现提高了天外星体存在生命的可能性。然后就是这句高亮句：take Jupiter’s moon Europa。这确实是一个例子，但后文对其描述用的是“may still bepossible”这样的文字。所以B选项speculation ，结合前文的empirical discovery是对其更准确的概括。A选项to be tested 原文是没有依据的。

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