Near many cities, contamination of lakes and rivers from pollutants in

Question

Near many cities, contamination of lakes and rivers from pollutants in rainwater runoff exceeds that from industrial discharge. As the runoff washes over buildings and pavements, it picks up oil and other pollutants. Thus, water itself is among the biggest water polluters.

The statement that contamination of lakes and rivers from pollutants in rainwater runoff exceeds that from industrial discharge plays which one of the following roles in the argument?

(A) It is a conclusion for which the claim that water itself should be considered a polluter is offered as support.
(B) It is cited as evidence that pollution from rainwater runoff is a more serious problem than pollution from industrial discharge.
(C) It is a generalization based on the observation that rainwater runoff picks up oil and other pollutants as it washes over buildings and pavements.
(D) It is a premise offered in support of the conclusion that water itself is among the biggest water polluters.
(E) It is stated to provide an example of a typical kind of city pollution.

DavidTutorexamPAL · Answer

The answer is D.  
We can solve this using the  Precise  approach, by simply analysing the passage and identifying its different parts. 
As indicated by the word "thus", the passage's conclusion is that water is among the biggest polluters. This is supported by the two previous sentences (of which the second supports the first).  Thus, the first sentence is a premise offered in support of the conclusion that water itself is among the biggest water polluters - answer D

akshaykotha · Answer

Hi David,

As you mentioned, the second sentence supports the first. With this proof, I selected C. Why is it not a generalization?

The structure: 
Sentence 1: Generalization
Sentence 2: Evidence
Sentence 3: Conclusion

guptakashish02 · Answer

Even i was confused between C and D.
But D was more direct . So i selected D.
What is wrong with option C?

VeritasPrepBrian · Answer

Good question, guys - the term "generalization" in a Critical Reasoning context (and this problem is an LSAT problem, and the LSAT uses it a ton) refers to a conclusion that makes a sweeping general claim when you only have information about a handful of data points. So like:

"I saw that Warren Buffet just sold off a lot of his positions,  so the stock market must be due for a big correction "

That conclusion is making a generalization - a broad claim about the market as a whole - from one data point.

or

"Exit polling from Springfield County has Candidate A leading by a 10% margin,  so Candidate A will likely win the national election "

Here you're generalizing about the election as a whole from just one county, which may not be representative of the nation as a whole.

In the question here, the sentence in question isn't a conclusion, so it's not a generalization. Now, the conclusion (the third sentence) could be considered a generalization because the evidence for it in sentence 1 is "in many cities" (a handful of data points) and the conclusion itself is broader. But the fact given in statement 1 isn't the generalization...it's the evidence from which a generalization could later be made.

akshaykotha · Answer

Thanks for the input  VeritasPrepBrian .

Actually the 'many cities' part is the swindled part in option C. But based on the order of first and second sentences, C can be eliminated.

VeritasPrepBrian · Answer

Not sure exactly what you mean but I wouldn't dismiss my mini-lesson on generalization like that. C is wrong because the first sentence - the sentence the question asks about - just isn't a generalization. It's provided as a fact, not as a conclusion, so it can't be a generalization.

The second statement adds more clarity to the first, sort of explaining the process behind the fact, but they don't have a premise-conclusion relationship. They're both given as facts and the third sentence is clearly marked ("Thus") as a conclusion. "In many cities" is just part of the stated fact.

To even expand on that:

Say you had the argument: "It is extremely difficult for Democrats to win elections without a high level of turnout from voters under 30. But voters younger than 30  generally  do not vote in high numbers in midterm elections unless they are motivated by a particularly inspiring message. Thus in order to win in this upcoming midterm election, Democrats will need to create a particularly inspiring message."

Sentence two even includes the word "generally" here...but it's not a generalization because it's not a conclusion (the last sentence is). It's just given as a fact (a fact that happens to include the word "generally" similar to how the premise in the main argument of this thread includes the modifier "in many cities"). A huge part of the game on Critical Reasoning, and especially "Method of Reasoning" questions is delineating between premise and conclusion. That's my point above...I hope that helps.

venkivety · Answer

Thanks a lot.as you have cleared the doubt relating to the Generalization-Premise-Conclusion

Chinointhehouse · Answer

Why B is the wrong answer,there is nothing wrong in the meaning of B

ryanstarr · Answer

Essentially, it's that B misses the mark in terms of what the cited fact is being used to support. It's true that the sentence presents rainwater runoff as a thing that's more problematic than industrial pollution, but that fact is also being used to make a bigger point: that rainwater runoff (and thus rain) is among the biggest causes of water pollution.

Evidence is only ever presented in CR arguments to support a specific position (the author's conclusion or a counterclaim). So the correct answer needs to make that connection explicit. D does a better job of that.

Posted from my mobile device

WiziusCareers1 · Answer

1. Identify the Parts of the Argument

To determine the role of a statement, we first need to separate the "Conclusion" (what the author is trying to prove) from the "Premises" (the evidence used to prove it).
 Premise 1 (The statement in question):  Near many cities, rainwater runoff contamination exceeds industrial discharge.
 Premise 2:  As runoff washes over buildings and pavements, it picks up oil and other pollutants.
 Conclusion:  Water itself is among the biggest water polluters.

2. The "Why" Test

A common strategy in logical reasoning is to ask "Why?" after a statement to see if it is a conclusion.
 Why is water itself among the biggest polluters? 
Because the contamination from rainwater runoff is even greater than that from industries, and because it picks up pollutants from city surfaces.
Since the statement in question provides a reason for the final claim, it acts as a premise.

3. Analysing the answers

(A) Conclusion:  This is incorrect because the statement is not being proved; it is being used to prove the final sentence. The final sentence (water is a polluter) is the "point" of the passage.

(B) Evidence for a "more serious problem":  While it mentions "exceeds industrial discharge," the argument does not go so far as to claim it is a "more serious problem." In LSAT logic, "more contamination" does not always mean a "more serious problem" (industrial chemicals could be 10x more toxic even in smaller amounts). This answer adds extra judgment the text doesn't contain.

(C) Generalization:  The statement is presented as a factual comparison, not a generalization derived from the specific observation of picking up oil.

(D) It is a premise offered in support of the conclusion  that water itself is among the biggest water polluters: This is correct because the statement provides a factual comparison (runoff vs. industrial discharge) that serves as the logical foundation for the final claim. Since the author uses this comparison to justify the idea that water is a "top-tier" polluter, the statement functions as a premise. The argument follows a "Premise + Premise → Conclusion" structure, and this statement is the primary evidence for the "size" of the pollution.

(E) Typical kind of city pollution:  The statement is a comparative claim between two sources of pollution, not just a single "example" of one.

WiziusCareers1 · Answer

1. Identify the Parts of the Argument

To determine the role of a statement, we first need to separate the "Conclusion" (what the author is trying to prove) from the "Premises" (the evidence used to prove it).
 Premise 1 (The statement in question):  Near many cities, rainwater runoff contamination exceeds industrial discharge.
 Premise 2:  As runoff washes over buildings and pavements, it picks up oil and other pollutants.
 Conclusion:  Water itself is among the biggest water polluters.

2. The "Why" Test

A common strategy in logical reasoning is to ask "Why?" after a statement to see if it is a conclusion.
 Why is water itself among the biggest polluters? 
Because the contamination from rainwater runoff is even greater than that from industries, and because it picks up pollutants from city surfaces.
Since the statement in question provides a reason for the final claim, it acts as a premise.

3. Analysing the answers

(A) Conclusion:  This is incorrect because the statement is not being proved; it is being used to prove the final sentence. The final sentence (water is a polluter) is the "point" of the passage.

(B) Evidence for a "more serious problem":  While it mentions "exceeds industrial discharge," the argument does not go so far as to claim it is a "more serious problem." In LSAT logic, "more contamination" does not always mean a "more serious problem" (industrial chemicals could be 10x more toxic even in smaller amounts). This answer adds extra judgment the text doesn't contain.

(C) Generalization:  The statement is presented as a factual comparison, not a generalization derived from the specific observation of picking up oil.

(D) It is a premise offered in support of the conclusion  that water itself is among the biggest water polluters: This is correct because the statement provides a factual comparison (runoff vs. industrial discharge) that serves as the logical foundation for the final claim. Since the author uses this comparison to justify the idea that water is a "top-tier" polluter, the statement functions as a premise. The argument follows a "Premise + Premise → Conclusion" structure, and this statement is the primary evidence for the "size" of the pollution.

(E) Typical kind of city pollution:  The statement is a comparative claim between two sources of pollution, not just a single "example" of one.

Near many cities, contamination of lakes and rivers from pollutants in

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GMAT Critical Reasoning (CR) Questions

Near many cities, contamination of lakes and rivers from pollutants in

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615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

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Perfect 805 Score Debrief by Julia

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