新Prep 74题请教！

sunflower82

74.(29534-!-item-!-188;#058&004138)



In a certain wildlife park, park rangers are able to track the movements of many rhinoceroses because those animals wear radio collars.When, as often happens, a collar slips off, it is put back on.Putting a collar on a rhinoceros involves immobilizing the animal by shooting it with a tranquilizer dart.Female rhinoceroses that have been frequently recollared have significantly lower fertility rates than uncollared females.Probably, therefore, some substance in the tranquilizer inhibits fertility.

In evaluating the argument, it would be most useful to determine which of the following?

A. Whether there are more collared female rhinoceroses than uncollared female rhinoceroses in the park

B. How the tranquilizer that is used for immobilizing rhinoceroses differs, if at all, from tranquilizers used in working with other large mammals

C. How often park rangers need to use tranquilizer darts to immobilize rhinoceroses for reasons other than attaching radio collars

D. Whether male rhinoceroses in the wildlife park lose their collars any more often than the park’s female rhinoceroses do

E. Whether radio collars are the only practical means that park rangers have for tracking the movements of rhinoceroses in the park

答案是C，但是我觉得没有一个答案是对的。关键词是“tranquilizer” inhibits “fertility”， C答案跟生育率一点关系都没有。谢谢！

sunflower82

帮人家回答了两道题，高手回答一下我的题。

2008115061

意见仅供参考~~~：  C: 原文的逻辑是：
犀牛如果老是掉了项圈---》一定比别犀牛被打更多的镇静剂---》导致不孕。
LZ觉得答案都不对，其实是因为无法攻击第二个逻辑链，即找不出除了镇静剂意外导致低rate的原因。
所以我们来攻击第一层逻辑，其实容易发现recollar的次数多，总的被镇静的次数不一定多，因为文章没说犀牛在其他时候是否被打镇静剂~这就是C

vivianzhili

这题 着眼于 比较的对象是  uncollared females.  如果选项c 的答案， 是very often ,那么uncollared femails 也有可能接受很多的镇静剂，那么和recollared 母犀牛没有拉开差距，就不能得出 结论是由于镇静剂里面的物质导致的低生育率

如果c 的答案是 not often ,那么 uncollared femails 不可能接受到镇静剂，那么就使得 镇静剂变为 可能的原因

注意： 结论用了个probably,   说明作者没有排除其他的原因。 选项c 也只能评估结论是否是可能的原因之一。

MeganZhao1

解释得很棒~！明白啦~！谢谢

bonfin

意见仅供参考~~~：  C: 原文的逻辑是：
犀牛如果老是掉了项圈---》一定比别犀牛被打更多的镇静剂---》导致不孕。
LZ觉得答案都不对，其实是因为无法攻击第二个逻辑链，即找不出除了镇静剂意外导致低rate的原因。
所以我们来攻击第一层逻辑，其实容易发现recollar的次数多，总的被镇静的次数不一定多，因为文章没说犀牛在其他时候是否被打镇静剂~这就是C

-- by 会员 2008115061 (2010/7/16 19:52:26)

thx