Critical Reasoning

C offers an explanation that's a different way of looking at it -- maybe the pollution levels didn't drop; maybe they just changed the threshold that determines when to call a smog alert. So that could explain the discrepancy too.

Karen wrote:The question isn't primarily why the pollution levels dropped in 1989. It's why pollution levels continued to rise after pollution control laws were enacted. "Between 1986 and 1989" is ambiguous -- it may not even include 1989 itself; it may mean only 1987 and 1988. In any case, the focus is clearly on the paradoxical rise in air pollution in 1987 and 1988, and B does not explain that. Even if the apparent drop in pollution in 1989 was due to better measurements, there's no explanation there of why pollution levels appeared to be rising in the previous two years despite new legislation.

D is not the answer because if the mayor exempted some local industries from the new regulations, that *would* help to explain why pollution levels continued to rise.

Hey Karen,

Here is my take on the argument. Am another proponent of choice D.

B says that a more accurate instrument was invented in DECEMBER 1988. Assuming that this was used next year (in 1989), the levels of carbon monoxide etc would be more precisely noted. It might be the case that instrument used earlier gave a higher reading and hence the higher number of smog alerts.

D says that in in 1988 the mayor exempt some industries from pollution checks. This action DOES NOT explain any rise in pollution. It also does not explain the reduction of smog alerts. Hence D should be the answer.

I'd love to hear your reasoning on this one.

Hi,
I think B gives an impression of helping identify as to why the levels went down after 1989.But as,others mentioned,it is never mentioned whether the new instrument was ever used.
Hence B should be the correct answer

Guy I want to reopen this thread...


I am completely lost here...I could see people proposing B or D..But I couldnt derive any logic here..

Plz help me out with some logical explanations...

gmatmachoman wrote:Guy I want to reopen this thread...


I am completely lost here...I could see people proposing B or D..But I couldnt derive any logic here..

Plz help me out with some logical explanations...

Who cares?!

This is a garbage 1000cr question. You may as well have some random person design a question, and then feel bad because you can't choose between two answers. Practicing on these questions can HURT you more than it can help you.

People think more questions, more practice, better off. But if the kind of questions you are working on are badly designed then a reason for why a right answer is right or why a wrong answer is wrong may not even be applicable on real GMAT questions. You might take away learnings that are bad information on the real test!

Hi gmatmachoman,

At any rate, choice D resolves the paradox: if a whole bunch of companies were exempt from measures that were supposed to stop them from polluting, it explains why pollutant levels were high up until and including 1988. Then, in 1989, after the scandal was exposed, these industries were no longer exempt from these measures, and so they had to abide by them--and that explains why the number of smog alerts declined.

Choice B does not resolve because increased accuracy could mean detecting previously undetectable ozone and carbon monoxide particles OR it could mean a reduced rate of mistakenly identifying particles as ozone and carbon monoxide even though they are not ozone and carbon monoxide. On the former interpretation, the paradox is deepened while on the latter interpretation, the paradox is resolved.

Mani_mba wrote:A question from 1000 CR.

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(D) In 1988 the mayor of Los Diablos was found to have accepted large campaign donations from local industries and to have exempted those same industries from air pollution control measures.
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IN D it accounts only for year 1988.SO what about 1987.Why does the pollution levels are on higher side in 1987?
IMO D partial accounts for the increased levels.

@Testluv ,I accept B has no role to play..But D also partial fulfills its job.

Am i missing anything here?

@Testluv...

Yeah 1000CR really hurts our prep on some cases....

Hi gmatmachoman,

In paradox questions, an answer choice resolves the moment it opens up the possibility of a logical explanation of the phenomenon.

In choice D, we learn that 1988 was the year that industries were found to be enjoying exemptions. This clearly allows for them to have been enjoying exemptions in years prior to 1988 as well. So choice D does provide an explanation. That is why it is wrong (remember is an EXCEPT question.)