[原创] GWD-5-38一个答案让我无法排除！

笨笨可可

以下是引用amber0919在2006-4-21 16:32:00的发言：
同意.A是反对前提了。

反对前提在逻辑的weaken中也是成立的阿。。

A==〉B，weaken，A根本就不会出现。。

kangdennis

cool

xiaoy791

以下是引用G_KEVIN在2004-10-10 22:14:00的发言：

Nitrogen dioxide is a pollutant emitted by automobiles.  Catalytic converters, devices designed to reduce nitrogen dioxide emissions, have been required in all new cars in Donia since 1993, and as a result, nitrogen dioxide emissions have been significantly reduced throughout most of the country.  Yet although the proportion of new cars in Donia’s capital city has always been comparatively high, nitrogen dioxide emissions there have showed only an insignificant decline since 1993.

Which of the following, if true, most helps to explain the insignificant decline in nitrogen dioxide emissions in Donia’s capital city?

1. More of the cars in Donia’s capital city were made before 1993 than after 1993.

2. The number of new cars sold per year in Donia has declined slightly since 1993.

3. Pollutants other than nitrogen dioxide that are emitted by automobiles have also been significantly reduced in Donia since 1993.

4. Many Donians who own cars made before 1993 have had catalytic converters installed in their cars.

5. Most car trips in Donia’s capital city are too short for the catalytic converter to reach its effective working temperature.

本题中，对于我来说，最难排除的是A，如果新车比旧车数量少的话，那么安装该种设备之后，似乎减少的不会太多，请各位大N帮忙解释一下，多谢！

如果文中把下面的这句话去掉，是否A也对？ －and as a result, nitrogen dioxide emissions have been significantly reduced throughout most of the country；

The passage strengthened the effectiveness of Catalytic converters,because they worked in most of the cities but not in Donia!

The passage told us Yet although the proportion of new cars in Donia’s capital city has always been comparatively high, that means any other city had more cars made before 1993 than the capital city did.

So the number of old cars is not the key!

克瑞斯

对lawyer解释有点疑问，如果我们极端考虑，整个城市只有1台93年以后的车，当然排污不能减少很多，这样A是说的通的。
A错的原因是和题目表述冲突了，题目已经说了该城市93年后的车比例很高，不能反驳题目已经给出的fact,所以A错。