困惑不解: LSAT-S4-I-12

jq_jou

12. Impact craters caused by meteorites smashing into Earth have been found all around the globe, but they have been found in the greatest density in geologically stable regions. This relatively greater abundance of securely identified crater in geologically stable regions must be explained by the lower rates of destructive geophysical processes in those regions.

The conclusion is properly drawn if which one of the following is assumed?

(B) Rates of destructive geophysical processes within any given region vary markedly throughout geological time.

(D) Actual meteorite impacts have been scattered fairly evenly over the Earth's surface in the course of Earth's geological history.

RIGHT ANSWER IS D). 怎么推出scattered fairly evenly ? 我觉得B)是正确答案, 因为vary markedly ,所以才回出现relatively greater abundance of securely identified crater in geologically stable regions
希望共同探讨

dorbear

论据有效型假设：

Lower rates of destructive geophysical processes in geologically stable regions => Greater abundance of impact craters；

（D） 中的 scattered fairly evenly 保证了论据的有效性，是因为论据才改变了原来分布evenly的状态。（B）只是原来论据的一个重复，属于无关选项。

个人意见！

[此贴子已经被作者于2003-9-23 0:18:55编辑过]

jq_jou

茅塞顿开,谢谢!

freegirl

ｄｏｒｂｅａｒ，

根据你在贝多芬与水银中的分析，我可不可以这样理解 B 呢：
如果取非Ｂ，　这地理破坏程度一样，直接否定了论据：Lower rates of destructive geophysical processes in geologically stable regions ，因此不对。
谢谢！！

dorbear

理解正确。

freegirl

谢谢！