A study conducted last year has indicated that striped bass

Question

A study conducted last year has indicated that striped bass in the Hudson River have more tumors than striped bass in rivers without industrial or agricultural development along their banks. In the previous two decades, significant progress had been made in clearing the Hudson of industrial pollution thought to promote tumorous growth, yet tumor levels in Hudson River striped bass are virtually unchanged from before this reduction.

Which of the following, if true, best helps to explain the situation explained above?

Which of the following, if true, best helps to explain the situation explained above?

A. There is a causal link between pollution from industrial and agricultural sources and the tumors on striped bass.

B. A change in the levels of industrial pollution has had little effect on most species of fish in the Hudson.

C. Efforts to clear the Hudson of industrial pollution have not removed all such pollution.

D. No other fish but striped bass are susceptible to the effects of industrial pollution.

E. The level of actual tumor-promoting agricultural pollution in the Hudson has remained relatively steady in the last 30 years.

tuanquang269 · Answer

Firstly, I chose C. However, I found this choice is a trap, and my detailed explanation is below:

A study conducted last year has indicated that striped bass in the Hudson River have more tumors than striped bass in rivers without industrial or agricultural development along their banks. In the previous two decades, significant progress had been made in clearing the Hudson of industrial pollution thought to promote tumorous growth, yet tumor levels in Hudson River striped bass are virtually unchanged from before this reduction.

Which of the following, if true, best helps to explain the situation explained above?

Which of the following, if true, best helps to explain the situation explained above?

A. There is a causal link between pollution from industrial and agricultural sources and the tumors on striped bass.  => this is the fact of the argument, and if this true, the tumor level should be changed, not unchanged as the argument said

B. A change in the levels of industrial pollution has had little effect on most species of fish in the Hudson.  => talk about fish, so irrelevant

C. Efforts to clear the Hudson of industrial pollution have not removed all such pollution. => this is a trap, even if it did not remove all pollution, partly reducing pollution still cause reducing in tumor levels

D. No other fish but striped bass are susceptible to the effects of industrial pollution.  => this is irrelevant, other fish is not in scope

E. The level of actual tumor-promoting agricultural pollution in the Hudson has remained relatively steady in the last 30 years. => this choice explains why the clearing progress does not affect anymore to the pollution of the Hudson river, so stripped bass does not decline.

mission2009 · Answer

Was caught in the same trap , selected C immediately, then realized my mistake. 
Nice explanation tuanquang269.

Chembeti · Answer

Although I agree that C is incorrect, I have a reason different from that of yours.

Even if the authorities have cleared the pollution completely, the problem would have persisted, because, authorities were mistaken with the material that was causing the problem and they did not remove the 'actual' material.

tuanquang269 · Answer

This is explanation type question. So, you should not assume another bridge, making more than one assumption that enable you go further.

Chembeti · Answer

Agreed. But my analysis is not based on any assumption but following info provided in question and answer choices:

Question part: "....pollution   thought   to promote tumorous growth...."
Answer choice (E): "The level of   actual   tumor-promoting agricultural pollution in the Hudson has remained relatively steady in the last 30 years."

mysterio · Answer

fact 1 : striped bass in hudson river have more tumors than striped bass in other rivers w/o argi dev.
fact 2 : significant progress have been made in cleaning the hudson river yet tumor levels are virtually unchanged.

it was supposed that industrial pollution caused tumor but that was not the case. Thus possible answer could be that something else might be causing tumor rather than industrial pollution or pollutant are not removed during cleaning. Lets check options to find the answer

A. There is a causal link between pollution from industrial and agricultural sources and the tumors on striped bass.  if this is the case then tumors should have reduced on cleaning hudson river

B. A change in the levels of industrial pollution has had little effect on most species of fish in the Hudson.  what if striped bass does not belong in fishes counted under most speices. Could be a probable contender if we coudl not find a better option

C. Efforts to clear the Hudson of industrial pollution have not removed all such pollution. => this is a trap, even if it did not remove all pollution, partly reducing pollution still cause reducing in tumor levels

D. No other fish but striped bass are susceptible to the effects of industrial pollution.  if this was true then tumors cases in striped brass shoudl have dropped on cleaning Hudson river

E. The level of actual tumor-promoting agricultural pollution in the Hudson has remained relatively steady in the last 30 years.  this explain that despite the cleaning of river tumor causing pollutants are still existant. IMO correct answer

raviram80 · Answer

I have two comments based on this argument

1. In the argument it mentions industrial or agricultural. In the conclusion it mentions only industrial and the choice E that you are referring to as correct, it mentions only agricultural .

2. Choice C only mentions industrial pollution as does the conclusion. Is this the difference between C and E and leading to discrepancy in the conclusion.

Thanks

Chembeti · Answer

a very valid point, ravi. good catch :-D

Sarang · Answer

Its an easy E.

As per answer choice C, efforts are made to reduce the pollution over the Hudson river. The statement mentions the efforts are not adequate to clear the pollution. However, with the pollution reduction the result would have been reduced tumor on the bass which is not the case as per the original sentence stem.

tuanquang269 · Answer

Haha, I agree with you. That's my fault. Thank for correcting me :D

sourabhk9 · Answer

As per the argument, tumors in striped bass is because of two factors, which are Agricultural and Industrial pollution. Although significant steps have been taken to reduce the levels of Industrial pollution in Hudson river, the incidences of tumor have not decreased. Thus it is possible that Industrial pollution is not the reason for the tumor in stripped bass.
Also, it is clear that the argument nowhere mentions that steps have been taken to reduce agricultural pollution.
Now evaluating the options:
 A. There is a causal link between pollution from industrial and agricultural sources and the tumors on striped bass.
 This weakens the argument as it implies that Industrial pollution leads to tumors on striped bass

B. A change in the levels of industrial pollution has had little effect on most species of fish in the Hudson.
 Notice the word 'MOST' and it not necessarily includes the species of Fish in question, i.e Striped bass. Hence out.

C. Efforts to clear the Hudson of industrial pollution have not removed all such pollution.
 Notice the word 'ALL'. The argument mentions that significant industrial pollution has been reduced and it's possible that most of it is reduced if not all

D. No other fish but striped bass are susceptible to the effects of industrial pollution.
 This weakens the argument as it implies that Industrial pollution is the cause.

E. The level of actual tumor-promoting agricultural pollution in the Hudson has remained relatively steady in the last 30 years. 
 This presents the alternative cause of the failure of reduced Industrial pollution and is the correct answer

hdwnkr · Answer

The struggle may be between E and C.

C states that the efforts have not removed all the pollution. They might have removed 99% of them.

E makes it clear that the efforts have not worked on the root cause.

Hence E

Nightmare007 · Answer

A study conducted last year has indicated that striped bass in the Hudson River have more tumors than striped bass in rivers without industrial or agricultural development along their banks. In the previous two decades, significant progress had been made in clearing the Hudson of industrial pollution thought to promote tumorous growth, yet tumor levels in Hudson River striped bass are virtually unchanged from before this reduction.

Which of the following, if true, best helps to explain the situation explained above?

Analysis: 
 Stripped bass (a species of fish) that is present in river H has tumor issue.
 River H has lot of agricultural and industrial areas along banks.
Paradox: From last 2 decades, People tried to reduce tumors by cleaning MOST industrial pollution.
 But in VAIN.
Presumption: Pollution made a genetic change in Fish, making them MORE susceptible to tumors. 
 Cleaned industrial pollution what about the agricultural pollution?
 The effect of cleaning might take more than 2 decades to show up.

Which of the following, if true, best helps to explain the situation explained above?

A. There is a causal link between pollution from industrial and agricultural sources and the tumors on striped bass. -  It more tightens the paradox. If there is link, why didn't it decrease?

B. A change in the levels of industrial pollution has had little effect on most species of fish in the Hudson. -  little effect (Near to None) on MOST species . No one knows whether these S.Bass come under these species. - Ambiguous

C. Efforts to clear the Hudson of industrial pollution have not removed all such pollution. -  All such pollution is not removed? But significant progress is made according to stimulus, So it has to impact somewhat. - OUT
 
D. No other fish but striped bass are susceptible to the effects of industrial pollution. -  if they are the ONLY fish that are susceptible, It doesn't give any explanation. Furthermore, It partially tightens the paradox saying that Industrial pollution will affect S.Bass and when it is cleaned to high degree, It still did not change the tumor levels.
 
E. The level of actual tumor-promoting agricultural pollution in the Hudson has remained relatively steady in the last 30 years.
  Exactly, What if the tumor-promoting pollution is not industrial that is being cleaned but it is agricultural pollution, waste from pesticides, dead weeds, Mineralized water etc. Furthermore, It is inline with our second presumption. - ANSWER

gmat1393 · Answer

Hey nightblade354

Please change the tag from Strengthen to Resolve the paradox. Thanks!

Bunuel · Answer

_________________
Done. Thank you.

VerbalBot · Answer

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A study conducted last year has indicated that striped bass

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A study conducted last year has indicated that striped bass

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