#4 - Over the last few decades, public outcries against

[Administrator]

Complete Question Explanation

Must Be True. The correct answer choice is (E)

As a result of public outcry over pollution during the last few decades, stricter regulations have
been enacted. Those cities with the worst pollution problems three decades ago have experienced
significantly improved air quality which, the author says, would not have come about without those
strict regulations.

The question stem that follows the stimulus asks for the choice that is properly inferred based on the
statements from the stimulus.

Answer choice (A): This clever incorrect answer choice might be initially tempting, because the
cities that were the worst thirty years ago have greatly improved air quality today, but the author
provides no information about the city that has the worst air quality today, so this cannot be
confirmed by the statements from the stimulus, and this cannot be the right answer choice.

Answer choice (B): Although the cities that had the worst pollution have improved their air quality,
it is also possible that many other cities have seen their air quality decrease in quality. This choice
cannot be confirmed by the information from the stimulus, so it fails the Fact Test and should be
ruled out of contention.

Answer choice (C): The author provides no information about the source of the public outcry
discussed in the stimulus, so there is no way to know, based on the stimulus, where most of those
outcries, came from, and this cannot be the right answer to this Must Be True question.

Answer choice (D): The cities that were the most polluted three decades ago have much better air
quality today than they did back then, but the possibility remains that those are still the most polluted
cities. Since this choice cannot be confirmed by the facts in the stimulus, it cannot be the correct
answer choice.

Answer choice (E): This is the correct answer choice. The author provides that those cities that
were the most polluted thirty years ago enjoy improved air quality which would not have happened
without stricter regulations, and that the public outcries brought about those stricter regulations. This
suggests that the public outcry led to the referenced improvements in air quality.

[ntusss]

Hi PowerScore Staff,

I have a question.

The last sentence said "this (improvement of air quality) wouldn't have happened without these stricter regulations", I thought it could be diagrammed as:

improvement of quality stricter regulations

And the first sentence said "public outcries brought about stricter regulations", which can be diagrammed as:

public outcries stricter regulations

If the above diagram is correct, then why is (E) inferable from the stimulus? Wouldn't it require us to reverse the logic of the last sentence? I mean, only if we think of the last sentence as: "stricter regulations improvement of quality" can we justify (E), right?

I don't know if I overthink. I know (E) is the best answer choices as the others have clear flaws, but I just want to make sure if my thought process is right. Thanks

[Adam Tyson]

The relationship between stricter regulations and public outcry is causal, not conditional, ntusss. You can see that by the use of the phrase "brought about" - that is a powerful indication of cause and effect. Because of that, we should not be using a conditional analysis on the question, but a causal one. If the public outcry caused stricter regulation, and if in the absence of those regulations we would not have had better air quality, it is reasonable to say that the public outcry had at least some effect on air quality. Not a conditional impact, but a causal one.

When both causal and conditional elements intersect, as seems to be happening more and more in recent tests, the more powerful causal language generally takes priority. Watch for that in future questions, it will surely happen again!

[Harneet]

Hi, I am confused as to why (A) is not correct. The stimulus states "The cities with the most polluted air...", wouldn't the city with the worst air pollution fall under this list? Or, does it not count since hypothetically this city started off as one of the 'better' ones, thus it was unaffected by the regulations, and is now the worst?

[Rachael Wilkenfeld]

Hi Harneet,

We can't draw any inferences about the cities with the most air pollution TODAY. Our stimulus only talks about cities with the worst pollution 30 years ago. It's entirely possible that cities with the worst pollution today are completely separate cities, and could have even greater levels of air pollution that there was in the polluted cities 30 years ago. The city with the worst air pollution in answer choice (A) would not have to fall into the category of the cities with the worst air pollution 30 years ago.

Hope that helps!
Rachael