Most of the power plants dispose of their waste water, used

Question

Most of the power plants dispose of their waste water, used to cool the plant, in wastelands or dried up rivers. Central water research institute, which monitors underground water quality for its consistency, report that uranium makes up for an ever increasing percentage of water pollutants in samples the institute collect. Hence, the efforts to decrease the amount of uranium in waste water that power plants dispose without treating are yielding no results.
 
Which of the following statements most seriously weakens the argument.

a.)The government has already spent millions of $$ to check contamination of ground water by uranium.
b.)The powerplants are now switching to better technologies which result in almost negligible uranium waste.
c.)With the application of various governement initatives to check water pollution,the proportion of major water pollutants such as arsenic, fluorides which used to be reported earlier has been considerably reduced.
d.)While the percentage of power produced by power plants has increased, the amount of uranium used is unchanged.
e.)Because uranium is radioactive in nature,most of the power plants are using certain technologies that can control and limit uranium's radioactivity.

KarishmaB · Accepted Answer

Report says that uranium makes up for an ever increasing percentage of water pollutants (i.e. the % of uranium in the total amount of pollutants is increasing). Note here that it doesn't say that % of uranium in water samples is increasing. 
e.g. if uranium made up 2% of the total pollutants before, it now makes up 3% of the total pollutants. 
What is happening to the % of total pollutants in the water is not known.

Conclusion: Efforts to decrease the amount of uranium are not working.

We want to weaken the conclusion i.e. we want to show that the efforts could be working.

Option (C) says that the proportion of other major water pollutants is decreasing. This could explain the increase in the proportion of uranium in the pollutants.

Think of values to understand this:

Say, % of total pollutants in the water sample is 5% i.e. in 100 lts of water, there's 5 lts of pollutants.
The 5 lt is made up of uranium, arsenic etc. Say, uranium is 1 lt and the others are 4 lts i.e. uranium is 20% of the total pollutants.
Now what if the amount of other pollutants go down from 4lts to 1 lt due to govt's efforts and amount of uranium goes down from 1 lt to 0.5 lt. The proportion of uranium has gone up to 33% of the total pollutants. 
Even though proportion of uranium has increased, the efforts are working since the amount of uranium pollutant went down. Hence we have weakened the conclusion.

adineo · Answer

As the highlighted part states that uranium is ever increasing; and the last line is that efforts to decrease uranium are failing. The best way to weaken this would be to prove that efforts are not failing and the reason that Uranium has increased in percentage is that other pollutants have decreased. Therefore answer is C

We are weakening it by providing an alternative reason to the conclusion.

ankit0411 · Answer

a.)The government has already spent millions of $$ to check contamination of ground water by uranium. -> doesnt matter what govt has already spent. 
b.)The powerplants are now switching to better technologies which result in almost negligible uranium waste - I found this a good contender but then it says the efforts have reduced after what power plants dispose off, without treating.
c.)With the application of various governement initatives to check water pollution,the proportion of major water pollutants such as arsenic, fluorides which used to be reported earlier has been considerably reduced.- gives an alternate route to understand why the % of uranium has increased ( this is because all other pollutants have reduced )
d.)While the percentage of power produced by power plants has increased, the amount of uranium used is unchanged. - doesn't give us anything substantial
e.)Because uranium is radioactive in nature,most of the power plants are using certain technologies that can control and limit uranium's radioactivity. - out of scope literally !

I went for B initially but then on reading the question again I came down the correct choice C.

rajathpanta · Answer

I still think B is the ans. How can C weaken the arguement.?? Can anyone explain.

ankit0411 · Answer

Hey, we need not worry that power factories are now switching to better methods to reduce uranium waste.
The stem talks about those factories, which produce waste without treating and what measures do govt take to reduce the % of uranium among the pollutants?

Make sense?

getgyan · Answer

+1 C

Premise - Most of the power plants dispose of their waste water, used to cool the plant, in wastelands or dried up rivers. Central water research institute, which monitors underground water quality for its consistency, report that uranium makes up for an ever increasing percentage of water pollutants in samples the institute collect

Conclusion - Hence, the efforts to decrease the amount of uranium in waste water that power plants dispose without treating are yielding no results.

Anything which weakens the conclusion is our answer i.e anything which proves that the efforts are yielding results is our answer

a.)The government has already spent millions of $$ to check contamination of ground water by uranium. (Irrelevant)
b.)The power plants are now switching to better technologies which result in almost negligible uranium waste. (Not related to governments effort)
c.)With the application of various government initiatives to check water pollution, the proportion of major water pollutants such as arsenic, fluorides which used to be reported earlier has been considerably reduced. (Percentage problem, this clearly shows that other contaminants has decreased because of governemnt initiatives and the uranium content remained the same, thus showing an increase in the overall uranium content. This is our answer)
d.)While the percentage of power produced by power plants has increased, the amount of uranium used is unchanged. (Irrelevant, nothing is given to relate the efficiency to population)
e.)Because uranium is radioactive in nature, most of the power plants are using certain technologies that can control and limit uranium's radioactivity. (Not related to governments effort)

:-D

schazamhuzzah · Answer

Amazing question.. Sometimes my head just shuts down when I do CRs ..I have no idea how to effectively answer every time. I guess one reason maybe because I dint spend enough time on them

amitgupta7587 · Answer

Answer C cannot be a correct option... Conclusion in detail is  Efforts to reduce the  amount of uranium in Waster Water generated from Power Plants  is not yielding results ... The conclusion does not talk about reducing the amount of Uranium in general, rather it is more concerned about the Waste Water -uranium content in detail.

KarishmaB · Answer

Responding to a pm:

Look at the argument:
"...report that uranium makes up for an ever increasing percentage of water pollutants in samples the institute collect."
Hence,  the efforts to decrease the amount of uranium in waste water that power plants dispose without treating are yielding no results .

We are deducing the conclusion (underlined) from the given data. When we add option (C) to the mix, we cannot make the conclusion anymore. It is possible that the efforts to control Uranium are yielding results but the efforts to reduce other pollutants are also yielding results. Hence (C) certainly weakens our conclusion. Remember, our conclusion is still possible. Just that it is weaker now.

abrakadabra21 · Answer

Most of the power plants dispose of their waste water, used to cool the plant, in wastelands or dried up rivers. Central water research institute, which monitors underground water quality for its consistency, report that uranium makes up for an ever increasing percentage of water pollutants in samples the institute collect. Hence, the efforts to decrease the amount of uranium in waste water that power plants dispose without treating are yielding no results.

Which of the following statements most seriously weakens the argument.

Which of the following statements most seriously weakens the argument.

power plant => dispose water 
uranium increase % of water polluyant
so the efforts to decrease the amount of uranium in waste water that power plants dispose without treating are yielding no results.

Prethinking:-
1> must be other reason for increase in U in water, may be some other industry that dispose water into the water
2> or if there is no effort, U would have been more. so atleast some effect of treatment.

C. With the application of various governement initatives to check water pollution,the proportion of major water pollutants such as arsenic, fluorides which used to be reported earlier has been considerably reduced.

So if A, F has decreased and that is even if U is decreased it's % has increased.

chesstitans · Answer

Although the source of this question is unclear, the question ins interesting.
The answer is C by using POE.
Also, the pattern in C is that the fact is misinterpreted.

sagarraj1986 · Answer

Got it wrong, but lovely question.

Posted from my mobile device

SonalSinha803 · Answer

Narrowed down to B and C. But to me neither make much sense. I feel the options are of a very poor quality. When the argument specifically says that uranium is not being treated and the plants have failed in treating them, how can we put C as an answer saying that your argument is weak because they are treating other major pollutants. 
But, damn they are still not treating Uranium.

Not really convincing....B and C are both so incorrect.

Sent from my Lenovo K53a48 using  GMAT Club Forum mobile app

Mavisdu1017 · Answer

Hello expert,
Throw some light on D? Thanks in advance.
The conclusion says the efforts to decrease the amount of uranium are not yielding, while C says other pollutants(arsenic/ fluorides), but not uranium. So what does it have to with the conclusion?
Also, D says plants produce more power with the same amount pollutant(uranium) emissions, so the efforts of cotrolling uranium are yielding.

NarayanaGupta007 · Answer

Mam, how to reject B ...the ques is about uranium waste in water and C is discussing about other wastes in water

VerbalBot · Answer

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Most of the power plants dispose of their waste water, used

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Most of the power plants dispose of their waste water, used

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