Driving the steep road to the mountain-top Inca ruins of Machu Picchu

Question

Driving the steep road to the mountain-top Inca ruins of Machu Picchu is potentially dangerous and hiking there is difficult. Now the Peruvian government is installing a cable car that will make access much easier, and hence result in a large increase in tourism. However, since the presence of large numbers of tourists tends to accelerate the deterioration of a site, installation of the cable car is certain to result in harm to the ruins.

Which of the following, if true, most seriously calls into question the argument?

(A) The daily number of tourists that are expected to take the cable car to Machu Piccu is smaller than the original resident population of Incas.

(B) The construction of the cable car terminal at Machu Picchu will require the use of potentially damaging heavy machinery at the site.

(C) Machu Picchu is already one of the most popular tourist sites in Peru.

(D) Natural weathering will continue to be a more significant cause of the deterioration of Machu Picchu than tourist traffic.

(E) The cable car will replace the tour buses whose large wheels and corrosive exhaust at present do significant damage to the site.

craky · Accepted Answer

Conclusion: Installation of the cable car is certain to result in harm to the ruins.
We are trying to weaken this conclusion.

E says: that the cable care will replace buses, which do damage now.

With their large wheels - cable car uses rails, so the road will not be damaged any more.
and corrosive exhaust - cable car runs on electricity, so no exhaust.

Furthermore, there won't be more tourists, only the means of transportation will be changed.

E weakens the argument and shows, that cable car will not result in harm to the ruins.

Divyadisha · Answer

To weaken the conclusion, we have to look for an option that states that installation of cable car will not result in deterioration.

A. The daily number of tourists that are expected to take the cable car to Machu Piccu is smaller than the original resident population of Incas.  We don't know how many tourists will cause the destruction of site.

B. The construction of the cable car terminal at Machu Picchu will require the use of potentially damaging heavy machinery at the site.  It supports the conclusion.

C. Machu Picchu is already one of the most popular tourist sites in Peru.  We are looking for an option that addresses damage to the site.

D. Natural weathering will continue to be a more significant cause of the deterioration of Machu Picchu than tourist traffic.  we want to knoe if cable car will cause more destruction.

E. The cable car will replace the tour buses whose large wheels and corrosive exhaust at present do significant damage to the site.  This means cable cars will infact be less damaging to the site. Correct answer

longhorn07 · Answer

(E)

The passage implies cars->more tourists->more damage. If (E) is true, then cable cars may actually result in less damage.

gmat1220 · Answer

I think we have to answer - why installation of "cable cars" will NOT result in damage. E is strengthening the argument not weakening.

amma4u · Answer

E - weakens by supporting the conclusion.

tip - for weakening questions look for logical gap. don't destroy the conclusion.

gmat1220 · Answer

Correct me. E is answering why the author thinks tour buses WILL destroy the site. Are you answering why cable car will NOT destroy the site. I don't think so. Furthermore the arg is dependent on the number of tourists visiting the place. Reread the stimulus - "cable car .... access much ..... increase in tourism... tends to accelerate the deterioration of a site". How can E be the answer?

E.g If the defense attorney is alluding that X is better killer than Y - does that precludes Y from assisting in the crime? Same here. Hence choice E does not hold water. It has to answer the question "why" cable car will NOT destroy the site. And premise should verify that cable cars are technologically advanced. I don't see the support.

vinzycoolfire · Answer

gmat1220 what you are asking for is a "perfect answer" to the question(something that says cable is eco friendly or something). wat u are saying about X and Y is indeed true. however in the absence of an answer that completely precludes cable cars,we shud choose one that is closest. and E does that. by saying cable cars are better than buses, we can saying cable cars are a better choice for manchu picchu. Maybe not the best, but definitely a better choice. So the conclusion is weakened(though only slightly).
Hope this helps!!
by the way ppl, wat is the source of this CR?

Steveewonder48 · Answer

Hi Guys ,

Pls forgive me if I am wrong But

Concl :

since the presence of large numbers of tourists tends to accelerate the
deterioration of a site so this is causing the harm . The impact of the Cable car or Tourist Bus is immaterial isin't it.

TO weaken the premise :
We need to show How the reduced people will improve the site beauty or reduce deterioration
Or
Since Machu Pichu is already crowded ... no matter what is done like cable cars or buses , the deterioration will continue immaterial to the transportation methods

So I think C is the answer But I am open to a debate since I may be wrong.

vinzycoolfire · Answer

You are wrong and forgiven :lol:

jus kidding....coming to your argument, "since the presence..." is not the conclusion,the conclusion is the second part which says "cable cars are bad for Machu picchu". disagree? read the sentence you have written above as conclusion. what is the "this"? that is the conclusion and the first part is the premise. not convinced? ask yourself what is a premise? and what is a conclusion?(since obviously u know these terms it is easy to define it). A premise supports the conclusion and a conclusion is something that the argument says is true because of the premise. now break down the sentence in question. "since the presence.." is saying the reason why "cable cars are bad for machu picchu". Now what is the conclusion? secondly,you almost never weaken the premise. It is the conclusion that you should attack, remember in every argument gmat will try invalidate the conclusion(main conclusion or sub conclusion) because an argument will have only one conclusion but many premises, it is easier to contradict that conclusion than to contradict several premises. Hope this helps!!

MHIKER · Answer

E. Because option E tells that the car is replacing the bus. As the car replacing bus, so the arguement is faulty.

Steveewonder48 · Answer

Superb Explanation !!!!!

I have to accept I am wrong !!

Definition of premise and Concl is real good !

U rock

vinzycoolfire · Answer

glad to help!! :-D

perhaps one day you might return the favor when i am stuck!! till then i'll be content if you give me a kudos by pressing +1 kudos under my display name. :wink:

AKG1593 · Answer

Option E.
If the cable cars will replace something already more damaging to the MP site,then the argument that cable cars will lead to deterioration is weakened.

Posted from my mobile device

nhattruong1302 · Answer

Explanation for choice D

Type: Weaken

Conclusion: installation of the cable => harm to the ruins

Assumption: installation of the cable is more harmful than current transportation used to get to the ruin.

Weaken the assumption: thr traditional way to get to the ruin is more harmful to the hostorical site

mbaprep2016 · Answer

I think key to answer this question "accelerate the deterioration of a site,"

What if X slow downs the deterioration of a site
Assumption :- X will not slow down the deterioration of a site
E clearly says the same.

Another way to see the problem is 
X will lead to Y 
Presenting another reason z will lead to Y , will not weaken the X as a reason.
in such cases we have check even X will be implemented , will it affect chances of Y

zvazviri · Answer

It appears your explanation is actually suited to E. Natural deterioration will happen anyway, so it is irrelevant to the argument about cable cars and more tourist traffic causing damage

Animesh2691 · Answer

But E does not says that buses do more damage than cable car
It only says that it does a significant damage
Are we supposed to assume it does more damage than cable car???
Experts plz help

kekid · Answer

This question has confused me.

Following words made it difficult for me to make the right choice. 
1) Access easier - If the access to the site is going to be easy, then tourists are responsible for the deterioration. Therefore, cablecars+moretourists = deterioration. Answer choice should counter that - which means BOTH (cablecars+moretourists) do not = deterioration. And if A is true, there is another cause of deterioration....in this case, answer A makes more sense.

2) The answer choice D says "natural weathering...MORE SIGNIFICANT CAUSE....which, if true (as mentioned by the question itself), will continue to be a major reason that deterioration takes place and not "cablecars+moretourists"

I am leaning more towards D versus E or A purely relying on the words "More Significant cause" because i feel all the three options ( E, A, D) if true can question the argument.

grb26 · Answer

Option E is the only one which actually weakens the argument as it has a reason to justify the use of cables.

Driving the steep road to the mountain-top Inca ruins of Machu Picchu

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GMAT Critical Reasoning (CR) Questions

Driving the steep road to the mountain-top Inca ruins of Machu Picchu

Prep Toolkit

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My Rewards