Which one of the following is an assumption on which the argument depends? - We need to find out the assumption.

(A) Urban pollution has not doubled in the past decade. - Even if urban pollution has doubled, how does that impact the conclusion? I am relying on data that says that even in cities with no urban pollution, the death rate has risen dramatically. So, even if urban pollution doubled, it will not mean that urban pollution is the cause of increased deaths because I have already countered this in the argument. Therefore, this statement is not the required assumption.

(B) Doctors and patients generally ignore the role of allergies in asthma. - Can you see what this option is doing? It is introducing one more factor which can explain the increased deaths. If we have one more possible cause, then our conclusion is weakened. We know that an assumption cannot weaken the conclusion; rather an assumption always supports the conclusion. Therefore, without further do, we can kick this option statement out.

(C) Bronchial inhalers are unsafe, even when used according to the recommended instructions. - My first impression is that this statement supports the conclusion. However, is it absolutely necessary for the conclusion to hold true? The answer is No. Bronchial inhalers can be safe when used according to recommended instructions. Such a case won't break down the conclusion. Probably, they are safe when used according to the instructions but a large number of people don't use according to the instructions. So, we have a case where the negation of the statement and the conclusion both will hold true. Therefore, the statement is not absolutely required for the conclusion to hold true. Therefore, this statement is incorrect.

(D) The use of bronchial inhalers aggravates other diseases that frequently occur among asthma sufferers and that often lead to fatal outcomes even when the asthma itself does not. - This statement, like option C, supports the conclusion; however, this statement also is not absolutely required for the conclusion to hold true. Even if the use of inhalers doesn't aggravate other diseases, it does not mean that inhalers are not the cause of increased deaths. Probably, the inhalers themselves are capable of causing deaths that they don't require help from other diseases :wink: So, this option statement is also not required assumption and hence incorrect.

(E) Increased urban pollution, improved recording of asthma deaths, and the use of bronchial inhalers are the only possible explanations of the increased death rate due to asthma. - This is the answer because we have already rejected four option statements and this is the last one, so we must select this. Just joking!

To understand why this is required assumption, we need to look at how the conclusion was derived. The conclusion was derived by saying that since A and B are not the possible reason, C is the cause of increased deaths. Do you understand this? If not, look back at the passage analysis.

So, we inherently assumed that only A, B and C are the reasons. If that is not the assumption and we thought D is also possible, then conclusion should have been: Since A and B are not the reasons, either C or D is the cause of increased deaths.

But that is not what we concluded. We concluded that C is the cause of increased deaths. So, we assumed that only three given reasons are possible.

I hope this helps

Thanks,
Chiranjeev
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Hi Chiranjeev,
I'm not able to get it clearly...!

As you've mentioned (rather as concluded) "since A and B are not the possible reason, C is the cause of increased deaths."..than how can we say that 'only three given reasons are possible' as A & B are already discarded by the author and that's why C comes up as the conclusion...Right?

Please help!

P.S: I actually chose D - as you've said "this statement also is not absolutely required for the conclusion to hold true" , I guess this sort of reasoning is pretty uncommon in GMAT CR... Let me know whether I'm wrong.
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Hi,

I don't really understand your query. I will still try to explain why option E is correct, but if the below explanation does not help, then please explain your doubt a bit more clearly.

Suppose I give you the following argument:

There are two possible explanations for Joe's success. One explanation is that he is super-smart. Other explanation is that he is very hard working. However, Tim is equally successful, but Tim is neither super-smart nor very hard working. Therefore, the actual reason for Joe's success is his ability to understand test maker's mindset.

What is the assumption in this argument?

The argument first tells two possible explanations, A and B, for Joe's success. But then, it says that there is Tim for whom neither explanation works.

Then, the argument concludes that C is the actual explanation for Joe's success.

In other words, the argument presents two explanations A and B for Joe's success and then, it indicates that these explanation could not explain Joe's success since they do not apply to Tim who is as successful as Joe. On the basis of this, the argument concludes that C is the reason for Joe's success.

Now, the first question that should comes to mind on reading the argument is that why not D, E, F, G, H etc could be reasons for Joe's success. Why does the author not consider these other possible explanations?

The reason is that the author assumes that only A, B, and C are possible explanations. So, when he sees that A and B cannot explain, he concludes that C is the reason.

Now, if you understand till now, then you can see that the argument I have constructed is very much parallel to the given argument and the same reasoning applies to explain why option E is correct.



I don't think this kind of reasoning is uncommon in GMAT CR. You do have strengtheners in assumptions questions in GMAT questions. These strengtheners strengthen the argument but are not absolutely required for the conclusion to hold true.

Thanks,
Chiranjeev
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Increased urban pollution, improved recording of asthma deaths - serve as counter premise in the argument. Option C hits directly on the author's conclusion so isn't C the correct answer?

This is an assumption type question, not an inference type question. Option C could be an inference, i.e. option C follows FROM the conclusion, not that it leads TO the conclusion.

Despite improvements in treatment for asthma, the
death rate from this disease has doubled during the past
decade from its previous rate. Two possible explanations
for this increase have been offered. First, the recording of
deaths due to asthma has become more widespread and
accurate in the past decade than it had been previously.
Second, there has been an increase in urban pollution.
However, since the rate of deaths due to asthma has
increased dramatically even in cities with long-standing,
comprehensive medical records and with little or no urban
pollution, one must instead conclude that the cause of
increased deaths is the use of bronchial inhalers by asthma
sufferers to relieve their symptoms.

Which one of the following is an assumption on
which the argument depends?
(A) Urban pollution has not doubled in the past
decade.
The premise clearly mentions that the pollution has changed for some cities but not for all the cities,But if we do negation test that the pollution has doubled even then the argument provides premise that the deaths due to asthma has increased in the cities where the the pollution has not increased.
(B) Doctors and patients generally ignore the role
of allergies in asthma.
This option is also discussed in the argument premise that the deaths happen even in the cities where the mediacal documentation is appropriate and the patients are aware of the problems.
(C) Bronchial inhalers are unsafe, even when used
according to the recommended instructions.
this does not make a assumption question since this is a clear conclusion and not leading to the conclusion.
(D) The use of bronchial inhalers aggravates other
diseases that frequently occur among asthma
sufferers and that often lead to fatal outcomes
even when the asthma itself does not.
The information provided in the option is clearly linking the premises and the conclusion of the argument and addresses why the bronchial inhalers are unsafe.but if we do the negation test that bronchial inhalers does not aggravate other diseases.....,but this does not beark the argument as one can say that the inhalers might aggravate the issues related to asthma itself.
(E) Increased urban pollution, improved recording
of asthma deaths, and the use of bronchial
inhalers are the only possible explanations of
the increased death rate due to asthma.
Increased urban pollution ,improved records and use of bronchial inhalers are only possible explanations and if we negate this that the argument will be invalid since it then suggest that ther may be naother reason for the deaths..so this is the correct answer.

Despite improvements in treatment for asthma, the death rate from this disease has doubled during the past decade from its previous rate. Two possible explanations for this increase have been offered. First, the recording of deaths due to asthma has become more widespread and accurate in the past decade than it had been previously. Second, there has been an increase in urban pollution. However, since the rate of deaths due to asthma has increased dramatically even in cities with long-standing, comprehensive medical records and with little or no urban pollution, one must instead conclude that the cause of increased deaths is the use of bronchial inhalers by asthma sufferers to relieve their symptoms.

Which one of the following is an assumption on which the argument depends?

(A) Urban pollution has not doubled in the past decade. -Even if the population increased, the increase doesn't explain the cause of asthma related deaths
(B) Doctors and patients generally ignore the role of allergies in asthma. -out of scope
(C) Bronchial inhalers are unsafe, even when used according to the recommended instructions. -Then these wouldn't have been prescribed by the doctors
(D) The use of bronchial inhalers aggravates other diseases that frequently occur among asthma sufferers and that often lead to fatal outcomes even when the asthma itself does not. -other diseases are out of scope
(E) Increased urban pollution, improved recording of asthma deaths, and the use of bronchial inhalers are the only possible explanations of the increased death rate due to asthma. -Correct

VeritasKarishma nightblade354 gmat1393 AjiteshArun GMATNinja
I choose D
why D is wrong ?
Second reason has been contradicted already so how it can be the reason

The use of bronchial inhalers aggravating other diseases is out of scope of our Argument.Remember the Conclusion is
Thats why option D is out of scope of our argument. In addition, you can see the detailed explanation at this link https://gmatclub.com/forum/despite-impr ... l#p1244388

VeritasKarishma DavidTutorexamPAL Please shed your views on option D.

Can you please bried how D is out of scope ?

An assumption on which an argument depends is something that must b true in order for the argument to be true: in other words, it is impossible that the argument be true and the assumption be wrong.
D certainly strengthens the argument, but is it an assumption? well, is it possible that the argument be true (the cause of asthma deaths is bronchial inhalers) but (D) be wrong (bronchial inhalers do NOT increase other diseases)? Absolutely! It may be that the inhalers have some totally different problem (maybe they're poisonous?? maybe they just don't work) unrelated to aggravating other diseases, and that the conclusion (inhalers > asthma) is true. Hence, D is not an assumption upon which the argument depends.
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