a logic question to discuss

juleyi

哪位兄弟姐妹帮分析一下逻辑思路：
In the arid land alomg the Colorado River, use of the river's water supply is strictly controlled: farms along the river each have a limited allocation that they are allowed to use for irrigation. But the trees that grow in narrow strips along the river's banks also use its water. Clearly, therefore, if farmers were to remove those trees, more water would be available for crop irrigation.
A. The trees along the river's banks shelter it from the sun and wind, thereby greatly reducing the anount of water lost through evaporation.
C. Many of the tree species currently found along the river's banks are specifically adapted to growing in places where tree roots remain constantly wet.
D. The strip of land where trees grow along the river's banks would not be suitable for growing crops if the trees were removed.

licheng

我来补充：
D中说砍了树的地方不能种庄稼，但是没有说农民要在那里种啊。。。
因此是不是可以认为D是正确答案的

dalaju

问题在于，同样的水量给予一块地，如何让庄稼多得（就是多种庄稼的问题）。
关键在两个方面：1）庄稼的多少；2）水分被吸收的效率
砍掉树，同样可以在原来树的一带和其他空地上种庄稼，可见D的理由不充分；
而A解释的是一个效率问题，树的减少使庄稼吸收水的效率降低，同样的水量不能支持多加的庄稼，所以是A。

tongxun

问题的中心在于：水量！
砍树是为省水，但砍了树水更少，岂不适得其反？

juleyi

the key is A.
any brother or sister can explain the logic here in detail ?

daisych

I would choose A also.,what is the correct answer?

primefang

further reflection 确实是A 啊

tongxun

If weaken ：A。i am sure。
where are you find such a question。

juleyi

hehe ... primefang 兄弟，
是选weaken，但不选D。
不过本题我请教过2位 native PhD,也没有选对，直说很trick.
用排除法可以选出答案，但逻辑仍不很清晰。
哪位同仁再分析一下逻辑思路？

primefang

if weaken

I choose D