prep2-36

36.   (31643-!-item-!-188;#058&006431)

Traveler:  Southern Airways has a far worse safety record than Air Dacentaria over the past few years, in terms of both the frequency of accidents and the severity of accidents.  Therefore, although Air Dacentaria is slightly more expensive, I will choose it over Southern Airways for my flight from Pederton to Dacenta, since it is worth paying extra to have a safer flight.

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

(A) Air Dacentaria's flight from Pederton to Dacenta is nonstop, whereas Southern Airways' flight touches down in Gorinda on the way.

(B) Most Southern Airways flights, 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 Pederton to Dacenta, Southern Airways uses a different model of airplane, with a smaller capacity, than the model Air Dacentaria uses for its flights on the same route.

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

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

选了E，不明白B是怎么削弱的。我觉得E也可以啊，虽然SA经常发生事故，但实际上发生事故的比例是一样得，可能只是SA得航班数更多而已。

不明白，nn给看一下吧

因为B中说Southern Airways的大部分（注意most）的航班是从一个事故高发区的机场起飞的，但这个消费者要乘坐的航班，即from Pederton to Dacenta的，不是从这个机场起飞的。从而削弱了这个消费者的结论。

我明白B是一种削弱

那E呢????

原文只说事故的频数大（frequency），但是如果频率（ proportion ）小的话完全不能用来支持结论嘛

LZ也谈到这一点

盼NN指点

我也觉得E也可以解释~~！！！

而且明明B的解释就是要绕一个弯之才解释了的~~~

顶一下~~~

S 比 D的记录差，但是D的贵，所以虽然从某地到某地的机票D的贵，但是安全。

条件成立是S比D的记录差，B选项否定了条件的成立，即S航空公司的记录差是因为他大部分航线起降是在一个非常危险的机场上进行的。但是并不包括题干中需要买机票的这个某地到某地的航线，所以B选项是对的，LS要理解B选项的意思，MS你是理解错了