VERBAL REVIEW CR66 请教一道题~

bobotea

Hardin argued that grazing land held in common (that is，open to any user)would always be used less carefully than private grazing land．Each rancher would be tempted to overuse common land because the benefits would accrue to the individual，while the costs of reduced land quality that result from overuse would be spread among all users．But a study comparing 217 million acres of common grazing land with 433 million acres of private grazing land showed that the common land was in better condition．

65．The answer to which of the following questions would be most useful in evaluating the significance，in relation to Hardin's claim，of the study described above?
(A)  Did any of the ranchers whose land was studied use both common and private land?
(B)  Did the ranchers whose land was studied tend to prefer using common land over using private land for grazing?
(C)  Was the private land that was studied of comparable quality to the common land before either was used for grazing?
(D)  Were the users of the common land that was studied at least as prosperous as the users of the private land?
(E)  Were there any owners of herds who used only common land，and no private land，for grazing?

答案是C没什么问题
我的疑问在A。 我觉得A选项对study驳倒H的观点有影响（Did any of the ranchers whose land was studied use both common and private land?) 如果没有人用private+common land 的话，那岂不是从根本直接否定了HARDIN的观点：人们用common land 比较careless？因为他们根本不会去用~

不知道怎么回事= =， 求NN解答~

bobotea

或者这么说，如果这个study很偏激的之选了那些只用common或private land 的人，不就本身说明了这个study 的可信度不高嘛。。？

Dianakisscat

我觉得LZ想偏了。

LZ在解题过程中加入了自己假设：
ALL ranchers will use BOTH common and private lands.

但是在原文中是没有提到这个假设的，原文只是说：
Hardin 认为 ranchers prefer common lands to private lands.

完全可能出现“ranchers only use common lands”和"ranchers only use private lands"这两种情况.