求助 旧prep cr2 36

coffee0921

Traveler:  Southern Airways has a far worse safetyrecord than Air Dacentaria over the past few years, in terms of both thefrequency of accidents and the severity of accidents.  Therefore, although Air Dacentaria isslightly more expensive, I will choose it over Southern Airways for my flightfrom Pederton to Dacenta, since it is worth paying extra to have a saferflight.                  

Which of the following, if true,casts the most serious doubt on the traveler's argument?

(A) Air Dacentaria's flight fromPederton to Dacenta is nonstop, whereas Southern Airways' flight touches downin Gorinda on the way.

(B) Most Southern Airwaysflights, but not its flight from Pederton to Dacenta, use Sarmouth airport,which because of its mountainous location is one of the world's most dangerous.

(C) For its flights from Pedertonto Dacenta, Southern Airways uses a different model of airplane, with a smallercapacity, than the model Air Dacentaria uses for its flights on the same route.

(D) Only in the last few years hasthe cost of flying from Pederton to Dacenta been more expensive on AirDacentaria than on Southern Airways.

(E) Although the frequency of accidents isgreater on Southern Airways, on both airlines the proportion of flights thathave accidents is very small.


参考了很多之前的讨论帖，还是不太明白，虽说通过对A、B两个事物的某一特定方面进行比较，而推出A优于B之类的结论，这样的结论要建立在这个前提上——这两个事物的其他方面必须同质或相似，才能评出个孰优孰劣。但这道题的B选项，说因为S机场很危险的原因，如何能够weaken原文的比较，我认为机场很危险导致的飞机事故率高也算作是S的问题啊~~而且，就算从P到D的航线不是在那个机场，也不能说明P到D就安全吖！


求NN解释！！！

coffee0921

The traveler thinks Air Dacentaria is "safer" than Southern Airways from Pederton to Dacenta. Theref ...
jaffa23 发表于 2011-5-12 06:42

    谢谢~
大概明白了。。。唉，又和GMAC的思路出现偏差了 T T

Fadaways

Premise:
1) SA has a worse safety record than AD over the past few years.
2) AD is more expensive than SA.
3) It is worth paying extra to have a safer flight

Conclusion:
I will choose AD over SA for my flight from Pederton to Dacenta.

The author assumes that the AD is safer than SA for flight from P to D. That might not necessarily be the case because the feature of a group might NOT be the feature of every member of the group. Although AD is overall safer than SA, it does not guarantee that AD is safer than SA in every single flight route.

jaffa23

"我认为机场很危险导致的飞机事故率高也算作是S的问题啊." That's right, so in other words, S的问题 是 机场很危险导致的. If there is no Sarmouth airport," 从P到D的航线不是在那个机场", Southern Airways should be as normal as other airlines.

The point we should focus on is "comparing safety" between airlines, don't consider that "Southern Airways is safe or not".

jaffa23

The traveler thinks Air Dacentaria is "safer" than Southern Airways from Pederton to Dacenta. Therefore, if we want to weaken it, there are two ways. 1. Air Dacentaria is worse than Southern Airways from Pederton to Dacenta. 2. Air Dacentaria and Southern Airways are equal from Pederton to Dacenta (not safer).

We aren't able to find any thing to support 1., either in the passage or in the choices. So we need to do 2.

A. C. E. has nothing to do with "safe", kick them out, we have B and E here.

E. does not mention anything about Pederton to Dacenta line, moreover, it proves that  Air Dacentaria is "safer" than Southern Airways. Although it uses total ratio, higher ratio still means "worse", no matter how small. Traveler's argument still stands.

B. states that there is a dangerous line for most of Southern Airways flights. It allows us to say that Southern Airways' accidents are because the dangerous location of most of their flights, not because their airplane or other issue. In other words, from Pederton to Dacenta (no Sarmouth airport invloved), we can not say which one is "safer" or "worse", they are the same.

coffee0921

B是正确答案，E是我选的= =

jaffa23

What is the correct answer? I would choose B rather than E...