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There are recent reports of apparently drastic declines in amphibian

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tkorzhan1995

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05 Nov 2021, 06:30

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GMATNinja, can you please explain why D should be eliminated for Q3?
It is noted in the 2nd par that chance events may lead to extinction.

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11 Nov 2021, 12:56

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Question 3

tkorzhan1995

GMATNinja, can you please explain why D should be eliminated for Q3?
It is noted in the 2nd par that chance events may lead to extinction.

Let's start by considering the question:

Quote:

3. It can be inferred from the passage that the author believes which of the following to be true of the amphibian extinctions that have recently been reported?

So the right answer should be something the author would believe to be true about "the amphibian extinctions that have recently been reported."

Let's now consider (D):

Quote:

(D) They have probably been caused by a combination of chance events.

In the second paragraph, the author discusses causes of extinction in general. Among these possible cause of extinctions, the author mentions chance events. But the author does not connect these chance events to the extinctions of amphibians. Nor does the author claim that chance events are the most likely cause of extinctions in general -- chance events are merely one possible cause, which the author cites as an example.

Since we have no reason to believe the author thinks these chance events caused the extinctions of amphibians that have recently been reported, (D) is out.

I hope that helps!

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GMATNinja VeritasKarishma
Why Q2 C is incorrect?
2. It can be inferred from the passage that the author believes which of the following to be true of the environmentalists mentioned in lines 5-6?
(C) Their certainty that population declines in general are caused by environmental degradation is not warranted.
3rd and 4th para - The author believes that decline could be due to normal fluctuations. So the claims made by environmentalist that declines are caused by degradation is not certain. The author does not believe this claim. Why C is incorrect then?

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05 Dec 2021, 22:01

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Sneha2021

The author doesn't say that the environmentalists claim of environmental degradation causing declines in population is not warranted.

In fact, the author himself mentions: "Persistent declines, especially in large populations, indicate a changed ecological context. ", "Unfortunately, long-term data will not soon be forthcoming, and postponing environmental action while we wait for it may doom species and whole ecosystems to extinction."
So he does agree that environmental factors are indeed involved in persistent declines.

Instead the author says that distinction needs to be made between endangered, persistent decline and apparent decline. Long term data gives us this distinction but that data is not available. So the "crisis situation" that the environmentalist's claim from recent reports is premature. The species may not actually be endangered.

Hence (C) is incorrect and (D) is correct.

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aragonn

singh8891 - What you have underlined is not the view of author, but it is the view of ' many environmentalists'. Author's view is given in P2. Author is not so sure about it. this is covered in P2. D is on these lines. Let me know if you need more clarity.

I have not completely understood the reason behind eliminating option C in question 2. Option C and option D look similar to me. It would be of great help if anyone could elaborate along these lines and clarify my doubt.

Thanks

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14 Feb 2023, 17:06

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Question 2

tanishkamishra

aragonn

Question 2 asks about the author's view on the environmentalists mentioned in lines 5-6. Here's what the author says in those lines:

"...many environmentalists have claimed that immediate environmental action is necessary to remedy this "amphibian crisis", which, in their view, is an indicator of general and catastrophic environmental degradation due to human activity."

Here's (C):

Quote:

Their certainty that population declines in general are caused by environmental degradation is not warranted.

There are a couple of issues with (C). For one, the environmentalists haven't made a claim about population declines "in general." Instead, they make a claim about amphibians specifically. So, the author wouldn't necessarily critique the environmentalists exactly like (C) does.

Also, the author's main quibble with the environmentalists isn't about whether environmental degradation is causing the declines -- the author is more concerned about whether there are really declines at all, and if so, how worrisome are those declines. If there ARE actual declines, the author seems pretty on board with the idea that environmental degradation is at least part of the cause -- such declines would "indicate a changed ecological context."

For these reasons, you can eliminate (C) for question 2.

I hope that helps!

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5. Which of the following most accurately describes the organization of the passage?

(A) A question is raised, a distinction regarding it is made, and the question is answered.
(B) An interpretation is presented, its soundness is examined, and a warning is given.
(C) A situation is described, its consequences are analyzed, and a prediction is made.
(D) Two interpretations of a phenomenon are described, and one of them is rejected as invalid.
(E) Two methods for analyzing a phenomenon are compared, and further study of the phenomenon is recommended.

hi GMATNinjaTwo, VeritasKarishma, MartyTargetTestPrep, AndrewN,VeritasPrepBrian,GMATRockstar
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avigutman, AndrewN,MartyTargetTestPrep

from P2&3, the author compares declining population and endanger population. in P4, authors proposes long-time data, so I think E match.

what's the problem with my reasoning ?

thanks in advance.

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14 May 2023, 07:40

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Question 5

zoezhuyan

5. Which of the following most accurately describes the organization of the passage?

(A) A question is raised, a distinction regarding it is made, and the question is answered.

(B) An interpretation is presented, its soundness is examined, and a warning is given.

(C) A situation is described, its consequences are analyzed, and a prediction is made.

(D) Two interpretations of a phenomenon are described, and one of them is rejected as invalid.

(E) Two methods for analyzing a phenomenon are compared, and further study of the phenomenon is recommended.

hi GMATNinjaTwo, VeritasKarishma, MartyTargetTestPrep, AndrewN,VeritasPrepBrian,GMATRockstar

KarishmaB

avigutman, AndrewN,MartyTargetTestPrep

from P2&3, the author compares declining population and endanger population. in P4, authors proposes long-time data, so I think E match.

what's the problem with my reasoning ?

thanks in advance.

You're right that the author compares "declining populations" with "endangered populations." However, that doesn't line up with what (E) says: "Two methods for analyzing a phenomenon are compared..."

Endangered populations and declining populations aren't methods for analyzing a phenomenon -- they're just useful terms to clarify the situation.

Eliminate (E) for question 5.

I hope that helps!

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aragonn

amphibians - live in water and land such as frogs, salamanders.
P1 - decline in population of A. Could be trend toward extinction.
P2 - evaluate P1. may be extinction, may be not.
p3 - biologists view, p decline = changed ecology .why? resolved - past fluctuations
p4 - long term data facts and its effects, if its too late then what - warning.

main idea - decline in A's population is discussed. past explored, facts evaluate for this decline.

1. The primary purpose of the passage is to

(A) assess the validity of a certain view -
(B) distinguish between two phenomena
(C) identify the causes of a problem
(D) describe a disturbing trend
(E) allay concern about a particular phenomenon

------------------------------------------------------

2. It can be inferred from the passage that the author believes which of the following to be true of the environmentalists mentioned in lines 5-6?
Pre-think - E are mentioned in P1. saying that if population decline then may be a trend toward extinction. So immediate environmental action is necessary. We need to look at author's view over this. Author's view is given in P2. Author is not so sure about it.

(D) They have drawn premature conclusions concerning a crisis in amphibian populations from recent reports of declines.

-----------------------------------------------------

3. It can be inferred from the passage that the author believes which of the following to be true of the amphibian extinctions that have recently been reported?
Inferrnce question, following one of the option must be true.

(A) They have resulted primarily from human activities causing environmental degradation. --- not sure.
(B) They could probably have been prevented if timely action had been taken to protect the habitats of amphibian species. --- could be could be not.
(C) They should not come as a surprise, because amphibian populations generally have been declining for a number of years. --- but recovered too
(D) They have probably been caused by a combination of chance events. ---- may be a natural thing with them.
(E) They do not clearly constitute evidence of general environmental degradation. --- true, not too extreme.

-----------------------------------------------------

4. According to the passage, each of the following is true of endangered amphibian species EXCEPT:
P2 has described a lot about this.
(D) Those with decreasing populations are the most likely candidates for immediate extinction. --- all correct except this .

----------------------------------------------------

5. Which of the following most accurately describes the organization of the passage?
refer to notes. --- a view is presented, evaluated, same view presented with diff angles, facts given and a warning

(A) A question is raised, a distinction regarding it is made, and the question is answered. ---- no question raised.
(B) An interpretation is presented, its soundness is examined, and a warning is given. --- this one is one same lines.
(C) A situation is described, its consequences are analyzed, and a prediction is made. --- 1 and 2 is right but last part is warning not prediction.
(D) Two interpretations of a phenomenon are described, and one of them is rejected as invalid. --- far from reality.
(E) Two methods for analyzing a phenomenon are compared, and further study of the phenomenon is recommended. ---- no.
----------------------------------------------------

6. Which of the following best describes the function of the sentence in lines 35-38 [Anecdotal reports of population decreases cannot distinguish among these possibilities, and some amphibian populations have shown strong fluctuations in the past.]?

Pre-thinking - This is presented to weaken the reports and conclusions drawn from that report presented in P1.

(C) To raise an objection to a view presented in the first paragraph ---- on the same line.

(A) To give an example of a particular kind of study
(B) To cast doubt on an assertion made in the previous sentence
(C) To raise an objection to a view presented in the first paragraph
(D) To provide support for a view presented in the first paragraph
(E) To introduce an idea that will be countered in the following paragraph

For question number 2 - why isn't "C" the answer? GMATNinja

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HI GMATNinja

Can you explain the the second question, I am confused between option C and Option D.

Thanks.

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Question 2

Ishita2000

For question number 2 - why isn't "C" the answer? GMATNinja

Ram_2001

HI GMATNinja

Can you explain the the second question, I am confused between option C and Option D.

Thanks.

I feel your pain on this one. (And felt your pain when evaluating (C) myself!) The key is subtlety in the language.

Let's take another look at (C):

Quote:

Their certainty that population declines in general are caused by environmental degradation is not warranted

On the surface, it certainly seems to make sense. The environmentalists have apparently concluded that the amphibian crisis has been caused by environmental degradation and so want to take action. The author is arguing that we need more data. So what's the problem?

Read it one more time. Notice the phrase "population declines IN GENERAL." Hm. The environmentalists are responding to the amphibian crisis. We don't know that they believe population declines are generally caused by environmental issues. So that's an issue.

Then there's the word "certainty." Are they certain? As opposed to maybe 95% confident, which would be enough to take action?

So pretty subtle stuff here, but those are the issues that make (C) inferior to (D), which specifically references the amphibian crisis, rather than general declines.

I hope that helps!

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I was a little confused by C because the language "raising objection" felt too strong, and instead the sentence seemed more like it was "casting a doubt"... how can I avoid getting caught up in such answers?

GMATNinja

You're not alone in asking about question #6...

Question 6

Question 6 asks about the function of the following sentence:

"Anecdotal reports of population decreases cannot distinguish among these possibilities, and some amphibian populations have shown strong fluctuations in the past."

(B) states that the purpose of this sentence is:

The previous sentence is:

"Even here, distinctions must again be made among declines that are only apparent (in the sense that they are part of habitual cycles or of normal fluctuations), declines that take a population to some lower but still acceptable level, and those that threaten extinction (e.g., by taking the number of individuals below the minimum viable population)."

The assertion made in this sentence is that "distinctions must again be made" among different kinds of declining species. The sentence discussed in question 6 says that we cannot make these distinctions using anecdotal reports.

So, the sentence in question doesn't cast doubt on the assertion made in the previous sentence -- the author still believes that we should make these distinctions. He/she just says that we can't do that with certain kinds of reports.

Compare that to (C):

In the first paragraph, the environmentalists claim that reports of amphibian population decline indicate "general and catastrophic environmental degradation due to human activity." By stating that certain reports can't give us all of the information we need to evaluate that claim, the author is raising an objection to the environmentalists' view.

To answer @coinsy's question -- yes, the first paragraph specifies that the environmentalists will only hold their claim if the reported population declines are real. However, being "real" doesn't help to determine which kind of population decline is occurring -- is it part of a normal fluctuation? Or one that will take the population to a low but acceptable level? Or will it truly threaten extinction?

In saying that this determination cannot be made, the author raises an objection even if amphibian populations are declining, as reported.

(C) is the correct answer to question 6.

I hope that helps!

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soniasw16

soniasw16

I completely understand your confusion about the language strength! This is actually a very common trap in RC function questions, and you're showing good instincts by being sensitive to word choice.

Key Insight: "Raising an objection" vs. "Casting doubt"

In GMAT RC, "raising an objection" doesn't necessarily mean strong, aggressive opposition. It simply means presenting a counterpoint or challenge to a previously stated position. Let me show you why (C) is correct and how to avoid this trap:

Step 1: Identify What's Being Objected To
Look at where each answer choice points:

Choice (B): "assertion made in the previous sentence" → This refers to the sentence about distinguishing types of declines
Choice (C): "view presented in the first paragraph" → This refers to the environmentalists' "amphibian crisis" claims

Step 2: Trace the Logical Relationship

The sentence states: "Anecdotal reports of population decreases cannot distinguish among these possibilities"
This sentence is NOT questioning the previous sentence's classification system. Instead, it's saying that anecdotal reports (which likely support the "crisis" claims in paragraph 1) are unreliable evidence. This objects to the first paragraph's crisis narrative by undermining its evidentiary basis.

The Critical Distinction:

"Casting doubt" (Choice B) would mean the sentence questions whether the classifications themselves are valid
"Raising an objection" (Choice C) means the sentence challenges the crisis claims by showing evidence problems

Strategy to Avoid This Trap:

Focus on structural relationships, not tone intensity: Don't get caught up in whether language feels "strong" or "mild"
Trace references precisely: When you see "previous sentence" vs. "first paragraph," map exactly what each refers to

Ask "What is being challenged?": The target of the challenge determines the answer, not the strength of the challenge

Quick Test for Function Questions: Instead of evaluating tone strength, ask yourself:

What claim/idea does this sentence address? (Here: the crisis claims from paragraph 1)
How does it address that claim? (Here: by showing the evidence is unreliable)
Where in the passage is that claim located? (Here: first paragraph, not previous sentence)

Remember: GMAT uses "objection" to mean any form of challenge or counterargument, regardless of intensity. Don't let the perceived strength of words distract you from the logical structure of the argument!

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23 Sep 2025, 14:02

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Question 6

soniasw16

You can raise a minor objection to something or raise a major objection to something. Likewise, you can cast a little bit of doubt on something or cast a whole lot of doubt on something.

In other words, the strength of either phrase isn't fixed, so it's impossible to say whether one is stronger than the other without additional context.

You could also argue that the author isn't necessarily trying to cast doubt on the environmentalists. In fact, the final sentence of the passage suggests that the author might AGREE that immediate environmental action is necessary. It's possible to raise an objection to something without casting doubt on it. For example, you might object to a specific part of an argument even though you agree with the overall conclusion of the argument.

Luckily, we don't need to worry too much about the relative strength of "cast doubt" vs "raise objection" or about the subtle difference in meaning between the two. In deciding between (B) and (C), it's more important to consider WHAT is being objected to and WHAT the doubt is cast on. Choice (B) does not cast doubt on (or raise an objection to) the previous sentence, so it must be eliminated regardless.

For more on that, check out this post: https://gmatclub.com/forum/there-are-re ... l#p2490745.

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passage 1= it provides the information about declining in amphibian population and extinction of a endangered amphibian species. also adds that environmentalist states that immediate environmental action is necessary to remedy this crisis. moreover they claim that its an indicator of general and catastrophic environmental degradation due to human activity.

passage 2= here author is primarily saying that we need to evaluate these claims. he says that dont confuse declining population with endangered one. in the last lin e he mentions that the probability of extinction depends on population size and its not entirely related to direction of change in that size.

passage 3= tells that biologist are more concerned with decline than extinction. then talks about some factors to be considered: declines that are apparent and decline to lower level but acceptable level.

passage 4= says that we dont have long term data to identify real declines and we are not going to get in the near future but we shouldnt be postponing the action otherwise situation will be worsen.

the passage begins with claim by environmentalist. then in succeeding paragraph, author evaluate claim and ends saying that despite not having long term data we should take action needed to prevent issue.

Ques 1=
A it states the above mentioned point properly. keep it.
B he is not distinguishing between two phenomenon.
C neither he is identifying cause of the problem
D nor he is describing disturbing trend.
E he is not showing any concern about particular phenomenon.

Ques 2=
A. the passage doesnt say anything about the data they have chosen to rely on.
B. passage is not about them being narrowed on single category at all.
C. off the table with word certain.
D. this looks out of context first but if you look in passage 2, author says that declining doesnt mean endangered one and there are chance events that could lead to extinction. so we can infer that environmentalist have drawn premature conclusion about crisis.
E. chance effects is actually mentioned by author and not environmentalists.

Ques 3=
A author never says that human activities were the reason.
B nothing about protection of habitat.
C he is not saying that its was coming and shouldnt be considered as suprise.
D chance events was mentioned in general and not directly towards amphibian.
E perfect. he says in 2nd and 3rd passage what else could be reason.

Ques 4=
only option D stands out .

Ques 5=
as per the earlier analysis, we know that author presented us with claim and then went onto evaluate the claim and in the end says that you know what we wont be having long term data and if we dont take action, situation would be worse.
only option B defines that construction very well.

Ques 6=
that portion says that reports of population decrease from here and there cant distinguish the possibilities. this is the ques he raised against the claim made by environmentalist in passage 1
A,D,E are clear elimination
for B, its not casting any doubt on previous statements at all. rather he used all those statements to come up with this highlighted text to go against the earlier drawn claim by environmentalists.

idkksh

There are recent reports of apparently drastic declines in amphibian populations and of extinctions of a number of the world's endangered amphibian species. These declines, if real, may be signs of a general trend toward extinction, and many environmentalists have claimed that immediate environmental action is necessary to remedy this "amphibian crisis", which, in their view, is an indicator of general and catastrophic environmental degradation due to human activity.

To evaluate these claims, it is useful to make a preliminary distinction that is far too often ignored. A declining population should not be confused with an endangered one. An endangered population is always rare, almost always small, and, by definition, under constant threat of extinction even without a proximate cause in human activities. Its disappearance, however unfortunate, should come as no great surprise. Moreover, chance events—which may indicate nothing about the direction of trends in population size—may lead to its extinction. The probability of extinction due to such random factors depends on the population size and is independent of the prevailing direction of change in that size.

For biologists, population declines are potentially more worrisome than extinctions. Persistent declines, especially in large populations, indicate a changed ecological context. Even here, distinctions must again be made among declines that are only apparent (in the sense that they are part of habitual cycles or of normal fluctuations), declines that take a population to some lower but still acceptable level, and those that threaten extinction (e.g., by taking the number of individuals below the minimum viable population). Anecdotal reports of population decreases cannot distinguish among these possibilities, and some amphibian populations have shown strong fluctuations in the past.

It is Indisputably true that there is simply not enough long-term scientific data on amphibian populations to enable researches to identify real declines in amphibian populations. Many fairly common amphibian species declared all but extinct after severe declines in the 1950s and 1960s have subsequently recovered, and so might the apparently declining populations that have generated the current appearance of an amphibian crisis. Unfortunately, long-term data will not soon be forthcoming, and postponing environmental action while we wait for it may doom species and whole ecosystems to extinction.
1. The primary purpose of the passage is to

(A) assess the validity of a certain view
(B) distinguish between two phenomena
(C) identify the causes of a problem
(D) describe a disturbing trend
(E) allay concern about a particular phenomenon

2. It can be inferred from the passage that the author believes which of the following to be true of the environmentalists mentioned in lines 5-6?

(A) They have wrongly chosen to focus on anecdotal reports rather than on the long-term data that are currently available concerning amphibians.
(B) Their recommendations are flawed because their research focuses too narrowly on a single category of animal species.
(C) Their certainty that population declines in general are caused by environmental degradation is not warranted.
(D) They have drawn premature conclusions concerning a crisis in amphibian populations from recent reports of declines.
(E) They have overestimated the effects of chance events on trends in amphibian populations.

3. It can be inferred from the passage that the author believes which of the following to be true of the amphibian extinctions that have recently been reported?

(A) They have resulted primarily from human activities causing environmental degradation.
(B)They could probably have been prevented if timely action had been taken to protect the habitats of amphibian species.
(C) They should not come as a surprise, because amphibian populations generally have been declining for a number of years.
(D) They have probably been caused by a combination of chance events.
(E) They do not clearly constitute evidence of general environmental degradation.

4. According to the passage, each of the following is true of endangered amphibian species EXCEPT:

(A) They are among the rarest kinds of amphibians.
(B) They generally have populations that are small in size.
(C) They are in constant danger of extinction.
(D) Those with decreasing populations are the most likely candidates for immediate extinction.
(E) The are in danger of extinction due to events that sometimes have nothing to do with human activities.

5. Which of the following most accurately describes the organization of the passage?

(A) A question is raised, a distinction regarding it is made, and the question is answered.
(B) An interpretation is presented, its soundness is examined, and a warning is given.
(C) A situation is described, its consequences are analyzed, and a prediction is made.
(D) Two interpretations of a phenomenon are described, and one of them is rejected as invalid.
(E) Two methods for analyzing a phenomenon are compared, and further study of the phenomenon is recommended.

6. Which of the following best describes the function of the sentence in lines 35-38 [Anecdotal reports of population decreases cannot distinguish among these possibilities, and some amphibian populations have shown strong fluctuations in the past.]?

(A) To give an example of a particular kind of study
(B) To cast doubt on an assertion made in the previous sentence
(C) To raise an objection to a view presented in the first paragraph
(D) To provide support for a view presented in the first paragraph
(E) To introduce an idea that will be countered in the following paragraph[/box_in][/box_out]

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