大全II-14

[CherrieLi]

14.A recent survey of all auto accident victims in Dole County found that, of the severely injured drivers and front-seat passengers, 80 percent were not wearing seat belts at the time of their accidents. This indicates that, by wearing seat belts, drivers and front-seat passengers can greatly reduce their risk of being severely injured if they are in an auto accident.

The conclusion above is not properly drawn unless which of the following is true?

(A) Of all the drivers and front-seat passengers in the survey, more than 20 percent were wearing seat belts at the time of their accidents.

(B) Considerably more than 20 percent of drivers and front-seat passengers in Dole County always wear seat belts when traveling by car.

(C) More drivers and front-seat passengers in the survey than rear-seat passengers were very severely injured.

(D) More than half of the drivers and front-seat passengers in the survey were not wearing seat belts at the time of their accidents.

(E) Most of the auto accidents reported to police in Dole County do not involve any serious injury.

答案是A, 想請問這一題的思路是? 看了很多遍, 題目都看得懂, 但卻選不出來...只知B跟C是無關選項, ADE要怎麼抉擇呢?

[lucyyeh]

這一題我覺得是有瑕疵的題目
但是要套答案A的話，我個人的解釋是這樣
結論是 wearing seat belts --> reduce risk
那麼如何得知呢？
在那個recent survey中，已得知有80%的因為沒有繫安全帶重傷, 那剩下的20%就是沒有重傷,
那剩下的20%做了什麼事得以倖免於難呢？就是A選所說的 ---> more than 20 percent were wearing seat belts at the time of their accidents.
(可是這裡more than 出來幹嘛...多出來的百分比怎麼解釋？盼高人指點）
D 選是縮小範圍的前提"80 percent were not wearing seat belts at the time of their accidents. " 不能解釋
E 無關壓！