GWD7-Q38求教哦，期待各位牛牛们

yidiyuehans

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?

• More of the cars in Donia’s capital city were made before 1993 than after 1993.
• The number of new cars sold per year in Donia has declined slightly since 1993.
• Pollutants other than nitrogen dioxide that are emitted by automobiles have also been significantly reduced in Donia since 1993.
• Many Donians who own cars made before 1993 have had catalytic converters installed in their cars.
• Most car trips in Donia’s capital city are too short for the catalytic converter to reach its effective working temperature.
  
  ANSWER: E
  WHY THE ANSWER SHOULD BE E?
  THERE IS NO INDICATION OF TEMPERATURE IN THE PARAGRAPH!

yidiyuehans

THX!

bloomers

The comparison in A cannot show the relative situation. For example, A has 100 cars made before 1993 and 98 cars made after 1993, since new cars are required to have a converter, it might decrease the emission rate because the difference is not great, so A can not explain the argument.

yidiyuehans

那A为何不可以解释这个问题呢？

bloomers

题干说“explain”所以是解释题，解释题的特点是偏好新信息，所以出现temperature不足为奇～