请教一道逻辑题-GWD-5-Q38

bontakuner

104.     (GWD 5-Q38)

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?
A. More of the cars in Donia's capital city were made before 1993 than after 1993.
B. The number of new cars sold per year in Donia has declined slightly since 1993.
C. Pollutants other than nitrogen dioxide that are emitted by automobiles have also been significantly reduced in Donia since 1993.
D. Many Donians who own cars made before 1993 have had catalytic converters installed in their cars.
E. Most car trips in Donia's capital city are too short for the catalytic converter to reach its effective working temperature.

标准答案是E，可以。但D为什么不对？题目中问为什么1993年DC城中的ND减少的不明显，D说因为老的汽车已经安装了CC这种减排装置，那么相当于本来DC城中的ND污染就轻，自然减少不明显。不是也很合理吗？

nobody910

你可能在理解D选项上有偏差
我觉得D选项是说那些购买1993年以前产的汽车的D城市民已经都装了减排装置了。这个意思里没有说他们装减排装置是在1993年以前吧？只是说那些1993年以前产的汽车都已经装了减排，这个安装大部分肯定是在1993年以后安装的，因为在1993年才开始要求新车装减排。
那么E选项取反，就是说D城里的汽车跑的路程足够长，减排装置可以达到一个高效的工作温度，那么，就无法解释为什么减排效果仍然不明显。
所以我觉得E才是最佳的解释原因
个人愚见，不知道对不对

felixroman

been required in all new cars in Donia 题中是这样说的，规定新车必须装。
所以之前旧车装不装都没关系，因为新车不装污染必然增多，而现在污染微降，所以D不能解释。

elsachialee

你可能在理解D选项上有偏差
我觉得D选项是说那些购买1993年以前产的汽车的D城市民已经都装了减排装置了。这 ...
nobody910 发表于 2012-10-15 21:22

同意，楼主注意，D里面写的是have had (现在完成时——现在已经装了)，跟had had（过去完成时——以前已经装了） 是有区别的。当时我也没注意到这点，多亏lz的提醒

DXDWSY

楼主想象力太丰富了，这都能想出来

bontakuner

嗯，感谢！的确如此。
当时做题时觉得E固然没问题，但D似乎更符合GMAC的出题风格，哈哈

sophialaw81

問個想不透的問題
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.  

1993 安裝後...有短暫的滅少...

那搭配E .. 又說      too short for the catalytic converter to reach its effective

感覺二句中有矛盾...一個是有安裝後有減少...E是  trip is too short以致於沒減少
(最大疑問在這裡)


throughout most of the country....整個country 降低......而非單指D城.
如果是這原因,我就了解了

dadaowuxing

我也选的D，但是一看D选项，根本没有说这些老车也装了converter的是D国的capital，，，坑爹