Unusually large and intense forest fires swept the tropics in 1997. Th

Question

Unusually large and intense forest fires swept the tropics in 1997. The tropics were quite susceptible to fire at that time because of the widespread drought caused by an unusually strong El Nino, an occasional global weather phenomenon. Many scientists believe the strength of the El Nino was enhanced by the global wanning caused by air pollution.

Which one of the following can be properly inferred from the information above?

Which one of the following can be properly inferred from the information above?

(A) Air pollution was largely responsible for the size and intensity of the forest fires that swept the tropics in 1997.
(B) If the El Nino in 1997 had not been unusually strong, few if any large and intense forest fires would have swept the tropics in that year.
(C) Forest fires in the tropics are generally larger and more intense than usual during a strong El Nino.
(D) At least some scientists believe that air pollution was responsible for the size and intensity of the forest fires that swept the tropics in 1997.
(E) If air pollution enhanced the strength of the El Nino in 1997, then it also contributed to the widespread drought in that year.

Source: LSAT

balaji4799 · Answer

This is an interesting question upon reading the options, there seems to be a confusion between D and E. D IMO seems like repetition of what was stated in the argument. E on the other hand seems well rounded since it talks about air pollution leading to stronger El Nino which in turn leads to drought. Hence I lean towards E. 
In fact other options A, B and C doesn't address the drought part of the argument which to me doesn't seem complete.

GYANENDRA88 · Answer

Unusually large and intense forest fires swept the tropics in 1997. The tropics were quite susceptible to fire at that time because of the widespread drought caused by an unusually strong El Nino, an occasional global weather phenomenon. Many scientists believe the strength of the El Nino was enhanced by the global wanning caused by air pollution.

Which one of the following can be properly inferred from the information above?

Which one of the following can be properly inferred from the information above?

(A) Air pollution was largely responsible for the size and intensity of the forest fires that swept the tropics in 1997. 
Incorrect coz many scientists believed something n it was not proven. So if it was a proven fact that air pollution was reason that made el nino more strong then i would have preferred this statement.

(B) If the El Nino in 1997 had not been unusually strong, few if any large and intense forest fires would have swept the tropics in that year.
Out of scope.

(C) Forest fires in the tropics are generally larger and more intense than usual during a strong El Nino.
Does not contain the whole argument.

(D) At least some scientists believe that air pollution was responsible for the size and intensity of the forest fires that swept the tropics in 1997.
Out of scope.

(E) If air pollution enhanced the strength of the El Nino in 1997, then it also contributed to the widespread drought in that year.
Correctly mentions that if the belief of scientists (i.e. Air pollution made el nino more stronger) was true then it also contributed to widespread drought.

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navderm · Answer

Air pollution was not responsible, it was a factor that enhanced the drought. The drought could is caused by weather, air pollution only enhanced it.
 
This can definitely not be inferred. There could have been other reasons for large and intense forest fires.
 
We are only told about the incident of 1997. Any occurrence could have had a very different outcome. We can't say that for sure.
 
This was an interesting one. It is a restatement of one of the sentences in the stimulus. That doesn't make it incorrect though. 
The reason I rejected this is, I contend, because air pollution is not responsible for the size and intensity of forest fire, it intensified the size and intensity. The drought was responsible for the size and intensity, which was because of El Nino enhanced by air pollution.
 
This is definitely correct.

I was confused between D and E. Finally chose E.

HASTOWINGMAT · Answer

This question was quite a difficult one. I was confused between B and C but the answer turned out to be E.
Can anyone please provide official reasoning to eliminate each choice.

Fdambro294 · Answer

I believe answering this question correctly is a product of whether you can catch one word in the last sentence.

“Many scientists believe that the strength of El Niño was ENHANCED by .......air pollution.”

This passage does NOT say that air pollution (which lead to global warming) was Primarily RESPONSIBLE for the strength of El Niño at the time. There could have been many other factors that “kicked off” such a strong El Niño. After the causation, air pollution and it’s global warming effect “strengthened” El Niño.

We are also told that this unusually strong El Niño caused the drought conditions that lead to the susceptibility of the tropics to fire.

For this reason, we can eliminate A and D. We can not infer that the air pollution was “largely responsible” for the significant fires that were a result of the drought conditions or whether ANY scientists believe that air pollution was “responsible” for the intensity of the fires. We only know that many scientists believe that air pollution enhanced El Nino’s strength.

E is correct because we are only told that many scientists “believe” that air pollution “enhanced” the strength of El Niño.

If these scientists are correct and air pollution and its effect of global warming enhanced the strength of El Niño, then:

Air pollution——-> enhances strength of El Niño, and the strength of El Niño ———-> caused drought.

A ———> B and B ———-> C

We can say that A had an impact or effect on C, which is what E is essentially saying.

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shauryahanda · Answer

The answer is E , that i do understand however

It is strictly wriien in powerscore that in GMAT if X is called the cause of an action , then it is the sole cause of action

Therefore - in this question if unusually strong el nino has been said to be the thing the forest fires cause of draught , then it can be said that if el nino would have been weaker , less forest fire would have happened

Attaching the quoted point

"When we discuss causality in the real world, there is an inherent understanding that a
given cause is just one possible cause of the effect, and that there are other causes
that could also produce the same effect. This is reasonable because we have the
ability to observe a variety of cause and effect scenarios, and experience shows us
that different actions can have the same result. The makers of the GMAT do not think
this way . When a GMAT speaker concludes that one occurrence caused another, that
speaker also assumes that the stated cause is the only possible cause of the effect and
that consequently the stated cause will always produce the effect. This assumption is
incredibly extreme and far-reaching, and often leads to surprising answer choices"

Fdambro294 · Answer

I believe the author of the book you are referring to was talking about causality in the context of an author making an argument in a CR passage.

This passage does not contain the usual argument made by an author (his opinion, suggestion, why he believes, etc.). We are given what these many scientists believe as a point of fact. Then, based on these facts, we are asked to determine which answer MUST be true.

We can not say for sure whether fewer forest fires would have occurred had there been a weaker El Niño. Maybe some other catalyst would have come along and caused more fires.

If this was the usual “premise ——>author’s conclusion” type of passage and the question asked us to find what the author must be assuming when she makes her conclusion, then what you quoted is right on point.

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shauryahanda · Answer

Fdambro294

Thank you for your help , i just have 1 question

i got confused thinking EL nino Has been stated as the cause of forest fire and scientists are making conjectures on what gave the El nino it's strength

You have mentioned that scientists believed that EL Nino caused the forest fire and hence the causal agreement falls.
That is where our understanding is differing as i believe EL nino as cause is established , just what gave it the additional unusual strength is on scientist conjecture

I hope you can understand my doubt

Thanks for your help

shristishreya1276 · Answer

Very Nice question. 
El-Nino is assumed to have an effect on the drought which in turn 
increases the chance of forest fire also air pollution is said to increase
EL-Nino so there are more chances for drought by air pollution which 
would in turn increase the forest fire. So, correct answer is E.

Crytiocanalyst · Answer

(A) Air pollution was largely responsible for the size and intensity of the forest fires that swept the tropics in 1997.
This cannot be infered since we don't kknow whether a direct relationship exist between air pollution and forest fire or that intermediatary factors play a more prominent role -Hence out

(B) If the El Nino in 1997 had not been unusually strong, few if any large and intense forest fires would have swept the tropics in that year.
Similar reasoning as A -Hence out

(C) Forest fires in the tropics are generally larger and more intense than usual during a strong El Nino.
We are not in a position to infer with the given premise may be that forest fire are part of the ordeal or that they happen regularly -Hence out

(D) At least some scientists believe that air pollution was responsible for the size and intensity of the forest fires that swept the tropics in 1997.
We cannot form a direct relationship similar to the reasoning of A and B there might be multiple intermeditaries -Hence out

(E) If air pollution enhanced the strength of the El Nino in 1997, then it also contributed to the widespread drought in that year.
Yes this can form a direct relationship since we can infer about the relationship from the premise of the passage 
Hence IMO E

MBAB123 · Answer

Hi, can anybody help me out with option E. I rejected E for the following reason -

The second sentence of the passage states -  The tropics were quite susceptible to fire at that time because of the  widespread drought caused by an unusually strong El Nino , an occasional global weather phenomenon . We know that the widespread drought was caused by an unusually strong El Nino, but did the drought occur because of the unusual strength of El Nino? Perhaps, a normal El Nino would've also caused a draught. An alternate example - My clothes got drenched because of the unusually heavy rainfall. My clothes could've been wet regardless of the strength/heaviness of the rainfall.

sssanskaar · Answer

Hi Brian123 , You have missed out on a very important modifier in your analogy. The correct analogy in your terms should look like this: My clothes got drenched COMPLETELY because of the unusually heavy rainfall, which in turn was enhanced by the incoming storm. Now, watch carefully- we can write this as: Storm -> Rain -> Complete wetness of clothes. Now, definitely, we can just say that Rain caused wetness of the clothes and not Storm. - Something that you also have mentioned. Storm can produce many other effects and not just Rain. So we can't say that Storm caused wetness of the clothes. We can only say that Rain caused it. But option E states that Storm CONTRIBUTED to the COMPLETE wetness. THIS IS DEFINITELY TRUE. Think about it. Because of the Storm, one of the many factors, rain happened, which in turn caused wetness of your clothes. We can say that rain was the cause of the effect - wetness, and not that the storm was the cause. But did the storm CONTRIBUTE to the wetness by any means? YES. By enhancing the area of wetness! How? By enhancing the intensity of the rainfall! You can infer Contribute as "something that is adding on the end result". Another example: If the firemen put oil instead of water in an already burning building, there will be an unusual widespread loss of life and property. Is the oil causing loss of life and property? NO. That is caused by an already burning building. But will adding the oil ADD TO THE EFFECT? YES! It will lead to AN UNUSUAL WIDESPREAD loss of life and property. In short, If A causes B and there is another factor Z which causes A such that when Z affects the intensity of A, the intensity of B also gets affected, we can say that Z CONTRIBUTES to the effect of B in the cases where the intensity of A has also been affected by Z.

8Harshitsharma · Answer

Option D is too broad; the strength of El-Nino might already have been unusual because of some other phenomenon which is not discussed in the passage. We can't infer based on the fact that air pollution ENHANCED El-Nino, that it was not already unusually strong. Eliminate D.

VerbalBot · Answer

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Unusually large and intense forest fires swept the tropics in 1997. Th

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