freemanfanmao wrote:
I feel like this is a really poorly constructed question.
First of all, a key piece of information given in the question-"Yet although the proportion of new cars in Donia's capital city has always been comparatively high"-is very confusing and introduces ambiguity. "New Car" can be interpreted in many different ways, even in the auto industry it is not a typically well defined term. "New Car" can mean new car sales each year, it can mean whether the car was bought new or used (in this case a car bought 10 years ago as new can still be a new car), it can mean new in relative terms (i.e. 2-year old is considered new but not 10-year old), it can also have many other meanings depending on how it's interpreted. Secondly, the meaning of the word "comparatively" is also unclear, presumably it means comparative to Donia's national level new car proportion, but it can also be interpreted as comparative to old car proportion in Donia's capital.
Lastly, I have yet to see a convincing explanation on why answer choice D is wrong, other than the one quoted below. As D seems to offer a pretty good logical explanation that, if many cars before 1993 already had the converter installed then having new cars with the converter will not have a big impact on the NO2 emission. All the experts' replies so far seem to miss the point, and the one below is the only sensible explanation I could find in this thread.
Susy426 wrote:
We need to find what makes Donia's City different from the rest of the country. D is wrong because it's talking about all Donians, not Donians who live in the Capital.
And if this is truly the intention of the questioner, then this goes back to my point that this question is just poorly constructed. As it offers a logically sound answer but traps you with small wording nuances.
I'm respectfully calling out all GMAT verbal experts to confirm my reasoning here regarding answer choice D, or to tell me that I was being completely nonsensical and subsequently give an alternative explanation.
Thanks.
"...it offers a logically sound answer but traps you with small wording nuances..." - That's GMAT CR in a nutshell! That's why reading precision is so important, as discussed in
this article and every CR video we've ever done, including
our most recent CR babble.
The explanation you quoted is spot-on. The passage very clearly indicates that there's a big difference between (1) what happened in the capital and (2) what happened in most of the country. Why is it that NO2 emissions barely declined in the capital while NO2 emissions were
significantly reduced throughout most of the country?
(D) fails to explain that difference. All else being equal, we would expect (D) to have the same impact on emissions everywhere in the country (including the capital). After all, if (D) is true, then ANY car (new or old) can have a catalytic converter and thus can have lower NO2 emissions. That means that the new tech should lower NO2 emissions everywhere, regardless of the proportion of pre-1993 vehicles... so why the discrepancy in the data?
(E) is the only one that explains the difference, so it's the only choice that works.
I hope that helps!