明天考试！急问一道RC题！谢谢！

GWD-24-30.

The author’s explanation of how deep events occur would be most weakened if which of the following were discovered to be true?

A.      Deep events are far less common than shallow events.

B.      Deep events occur in places other than where crustal plates meet.

C.      Mantle rock is more ductile at a depth of several hundred kilometers than it is at 50 kilometers.

D.     The speeds of both P and S waves are slightly greater than previously thought.

E.      Below 650 kilometers earthquakes cease to occur.

选D 还是B?

楼主MM快睡觉吧...明天还要考试...要保证充足的体力...

这个题目选择B, 定位在文章最后一段,

deep events occur in areas where one crustal plate is forced under another and descends into the mantle

如果这个deep events根本就不发生在crustal plate交界处, 就谈不上one is forced under another

所以这个解释被极大的削弱了,

D选项说P和S的速度比预期的快, 这个纯属无关, 因为根据第一段, 比较的是 P出现时间-S出现时间, 且P速度=S速度,

所以无论P和S的速度如何, 不会影响到这个时间差值, 这么说....应该清楚了吧...

速度睡觉....祝明天考试顺利...等着分享你的喜悦...呵呵

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