LSAT-6-2-16

16.   The ancient Romans understood the principles of water power very well and in some outlying parts of their empire they made extensive and excellent use of water as an energy sources. This makes it all the more striking that the Romans made do without water power in regions dominated by large cities.

Which one of the following, if true, contributes most to an explanation of the difference described above in the Romans’ use of water power?

(A) The ancient Romans were adept at constructing and maintaining aqueducts that could carry quantities of water sufficient to supply large cities over considerable distances.

(B) In the areas in which water power was not used water flow in rivers and streams was substantial throughout the year but nevertheless exhibited some seasonal variation.

(C) Water power was relatively vulnerable to sabotage but any damage could be quickly and inexpensively repaired.

(D) In most areas to which the use of water power was not extended other more traditional sources of energy continued to be used.（E）

(E) In heavily populated areas the introduction of water power would have been certain to cause social unrest by depriving large numbers of people of their livelihood.

这一题很晕啊，到底“large cities”是有水不能用？还是没有水根本用不了？如（E）选项所说，the introduction of water power和cause social unrest又有什么关系呢？觉得很奇怪呢

其他选项为什么又不对呢，比如（A），说古罗马人可以远距离给大城市供水，所以大城市不需自己使用water power，暗含那些大城市其实是有水而不用？

难道题目是说大城市为什么根本没有使用water power？或是别的？

请NN帮我分析一下题目的意图和各个选项吧，谢谢了：）

by depriving large numbers of people of their livelihood.

这句说明，使用水力导致失业，结果那些失去营生的人导致社会动荡。所以，城市不用水利。

大概明白了，谢谢你的回复：）