Irrigation runoff from neighboring farms may well have increased the

Question

Irrigation runoff from neighboring farms may well have increased the concentration of phosphorus in the local swamp above previous levels, but the claim that the increase in phosphorus is harming the swamp's native aquatic wildlife is false; the phosphorus concentration in the swamp is actually less than that found in certain kinds of bottled water that some people drink every day.

The argument is vulnerable to criticism on the ground that it

(A) makes exaggerations in formulating the claim against which it argues

(B) bases its conclusion on two contradictory claims

(C) relies on evidence the relevance of which has not been established

(D) concedes the very point that it argues against

(E) makes a generalization that is unwarranted because the sources of the data on which it is based have not been specified

chesstitans · Answer

I do not understand how to get the answer out of this question. Is there any general way to solve this question?

Aj558 · Answer

C

The evidence provided is not relevant.

Posted from my mobile device

arvind910619 · Answer

imo C 
easy one the two independent event are unrelated c correctly shows that.

abhishek31 · Answer

Hi, can someone explain why D is wrong?

NRJ11090 · Answer

Definitely C is the correct answer choice. In the given argument phosphorus content of bottled water is being compared with the phosphorus content of local swamp. The argument does not mention any point of relevance between the Phosphorus content of the bottled water and the swamp. Aquatic life forms are different from human beings. So, the comparison here is inappropriate. 
A- irrelevant 
B- there are no two contradictory claims in the argument. 
 C- CORRECT 
D- the author simply puts forward his claim and this claim is based upon a comparison between two different things.
E- irrelevant. No generalizations have been made.

rodri102 · Answer

D is incorrect as the facts in the stimulus are not arguing against the harm of phosphorus levels. It concedes with the claim that the increase in phosphorus is not harming the swamp's native aquatic wildlife. However, the argument does provide irrelevant evidence to support that claim. Specifically, the argument assumes that if phosphorus content is at an acceptable level in bottled water, then less concentration in the swamp, makes it acceptable there too. Thus, this evidence is not relevant to the argument. Answer choice C is correct.

vv65 · Answer

D says that the argument "concedes the very point that it argues against"

"concedes the very point that it argues against" 
means 
"accepts the same point that it is trying to refute"

The point the author is trying to refute is that "the increase in phosphorus is harming the swamp's native aquatic wildlife"

The author has not accepted this point anywhere, so D is wrong

He argues against this claim by saying that "the phosphorus concentration in the swamp is actually less than that found in certain kinds of bottled water that some people drink every day"

This info is irrelevant : the phosphorus levels may be safe for humans - that doesn't mean they are safe for aquatic wildlife in the swamp.
So the answer is C

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WiziusCareers1 · Answer

The core flaw in this argument is a  false analogy . It assumes that because a certain concentration of a substance (phosphorus) is safe for one biological system (humans drinking bottled water), it must also be safe for an entirely different ecosystem (swamp wildlife).

(A) Makes exaggerations in formulating the claim against which it argues 
This refers to a "straw man" fallacy, where an opponent's position is distorted to make it easier to attack. In this text, the author doesn't exaggerate the environmentalists' claim; they state it directly (that phosphorus is harming wildlife). The author's failure lies in their rebuttal, not in how they phrased the original claim.
 Why it's wrong:  The argument fails because of poor evidence, not because it misrepresented the opposing view.

(B) Bases its conclusion on two contradictory claims 
For this to be true, the author would have to state two things that cannot both be true (e.g., "The phosphorus levels increased" and "The phosphorus levels stayed the same"). Here, the author acknowledges the levels increased and compares them to bottled water. These two statements can exist simultaneously without a logical contradiction.
 Why it's wrong:  There is no internal logical conflict between the premises; the premises are consistent, just irrelevant.

(C) Relies on evidence the relevance of which has not been established 
This is the heart of the error. The author uses the safety of phosphorus for human consumption as evidence for its safety in a swamp ecosystem. However, the "relevance" is missing: humans and swamp wildlife (like fish, amphibians, or algae) have vastly different biological tolerances. A level of phosphorus that is healthy for a human could trigger an algal bloom that deoxygenates a swamp and kills all the fish.
 Why it's right:  The argument assumes "safe for humans = safe for swamp fish" without providing any evidence that these two things are comparable.

(D) Concedes the very point that it argues against 
This would mean the author accidentally proved that the phosphorus is harming the wildlife. While the author admits the phosphorus levels increased, they never admit that it is harmful. Admitting a trend exists is not the same as admitting the negative consequences of that trend.
 Why it's wrong:  The author stays firm in their conclusion that no harm is being done; they simply use a bad reason to support it.

(E) Makes a generalization that is unwarranted because the sources of the data have not been specified 
This choice suggests the flaw is about "anonymity" or "lack of citations" (i.e., not naming the brand of bottled water). In logical reasoning, an argument isn't necessarily flawed just because it doesn't name its sources, provided the logic holds. The primary issue here isn't where the bottled water data came from, but why we are talking about bottled water in the first place.
 Why it's wrong:  The flaw is one of logic and relevance, not a lack of specific data sourcing.

Irrigation runoff from neighboring farms may well have increased the

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Irrigation runoff from neighboring farms may well have increased the

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