There is only one major road, Freeway Z, that links County X and Count

Question

There is only one major road, Freeway Z, that links County X and County Y. The border of the two counties is primarily defined by a mountain range, over which the construction of new roads is severely restricted by environmental laws. A cost-effective solution to the problem of traffic congestion on Freeway Z is to build a commuter train tunnel through the mountain range. The successful implementation of this plan would cost far less than expanding the existing freeway and would also reduce the number of cars clogging the roads in both counties.

Which of the following, if true, could proponents of the plan above most appropriately cite as a piece of evidence for the soundness of their plan?

A. An effective commuter train tunnel between the counties would require major investment in mass transit within both counties.

B. The majority of all vehicles on the nation’s freeways are traveling from one state to another.

C. 60% of the cars on Freeway Z are driven by people who live in County Y and work in County X.

D. Many new freeways are being built in areas that are presently served by commuter trains.

E. A large proportion of the vehicles on Freeway Z are commercial trucks carrying transcontinental shipments.

parker · Accepted Answer

You're looking for an answer that could be used as further evidence for the soundness of the plan-- in other words, a new premise that will SUPPORT/STRENGTHEN the  conclusion  that successful implementation of the plan will  (1) cost less than freeway expansion and (2) reduce congestion in both counties.

(A) We're looking for something to help prove that the tunnel would cost LESS than freeway expansion. We don't know anything about the cost of freeway expansion (although the expansion sounds difficult, and probably expensive), but this choice makes the tunnel sound really expensive! Eliminate.

(B) If most vehicles on the freeway are taking interstate trips, then the tunnel linking County X and County Y would probably not reduce congestion in these counties, since the majority of that congestion is coming from vehicles that would stay on the interstate freeway. Eliminate.

(D) That's nice, but does it affect our conclusion? Who cares about "many" freeways -- we only care about Freeway Z, and Counties X and Y.

(E) Transcontinental trucks probably wouldn't be hugely motivated (or even know about) a direct tunnel between counties X and Y. This choice is out for the same reason that choice B is out.

If 60% of the traffic on the freeway is from people commuting between X and Y, then a commuter train between these two cities might well be an appealing solution to their transportation needs, and motivate them to abandon driving on the congested highway. Does this choice prove the conclusion? Absolutely not. But it does provide additional support (and the other answer choices have concrete flaws that knock them out entirely).

plumber250 · Answer

Hi Mun,

Here is my thinking as I went through this question... I hope it helps.

There is only one major road, Freeway Z, that links County X and County Y. The border of the two counties is primarily defined by a mountain range, over which the construction of new roads is severely restricted by environmental laws. A cost-effective solution to the problem of traffic congestion on Freeway Z is to build a commuter train tunnel through the mountain range. The successful implementation of this plan would cost far less than expanding the existing freeway and would also reduce the number of cars clogging the roads in both counties.

OK. So basic structure is that very expensive to build new roads between X & Y. So why not build a train instead, it's cheaper and would ease congestion.

Which of the following, if true, could proponents of the plan above most appropriately cite as a piece of evidence for the soundness of their plan?

So, this is a STRENGTHEN question. We're looking for something below that backs up the argument. So lets see what below suggests that trains would be better...

(A)An effective commuter train tunnel between the counties would require major investment in mass transit within both counties.

No. This is not correct. We're looking for things that make the train cheaper. This is providing extra costs for the train option. No good.

(B)The majority of all vehicles on the nation’s freeways are traveling from one state to another.

No. This is irrelevant. It talks about the nation, we're only interested in County X &Y.

(C)60% of the cars on Freeway Z are driven by people who live in County Y and work in County X.

Good. This looks good, the cars already on Z are used for commuting, so a train would serve them well. This suggests a train would be useful and successful

(D)Many new freeways are being built in areas that are presently served by commuter trains.

Irrelevant. This is not linked specifically to County X & Y.

(E)A large proportion of the vehicles on Freeway Z are commercial trucks carrying transcontinental shipments.
 No. This weakens. If this were true, a train would have little or no effect, as the transcontinental shipments would not be able to se it

Hope that helps. As others have said B is the tricky one, but key always to ensure the evidence provided is directly relevant to the situation described. In B this time that is not the case, as the answer choice talks about 'nation' whilst we're worried about County X & County Y

Bunuel · Answer

OFFICIAL EXPLANATION

Since construction of new roads between County X and County Y is severely restricted, this argument claims that building a commuter train between the counties is a more cost-effective way to reduce congestion on Freeway Z than expanding the existing freeway or building a new one. This plan will work only if people currently driving on the freeway are likely to use the new commuter train. If the congestion is caused largely by people driving between the two counties, then some of these people would likely choose to use the train instead, decreasing traffic congestion on the freeway.

(A) The cost associated with funding necessary mass transit in both counties, in addition to the expense of the tunnel itself, is an argument against, not for, the proposed commuter train tunnel.

(B) This plan addresses a very specific situation: traffic between two counties on a certain freeway. Information about the nation’s freeways in general is not relevant to this argument.

(C) CORRECT.  This statement shows that a majority of the cars on Freeway Z are driven by commuters. Commuters are more likely than other groups to use the proposed train tunnel; if so, fewer cars would travel on the freeway, and traffic congestion would decrease.

(D) This plan addresses a very specific situation: traffic between two counties on a certain freeway. New freeways that are being built elsewhere are not relevant to this argument. Even if this information were relevant to this situation, it would be an argument against the proposed commuter train tunnel, indicating that new freeway construction is necessary despite the existence of commuter trains.

(E) The information that Freeway Z is congested largely because of transcontinental shipments in commercial trucks, rather than commuters between the two counties, is an argument against the proposed commuter train tunnel. A large proportion of the vehicles on Freeway Z are commercial trucks, which will still travel that route even if the commuter train tunnel is built, so traffic congestion will be largely unaffected.

adishail · Answer

We are looking for something that will support the plan to build a train track.

NOT RELEVANT  A. An effective commuter train tunnel between the counties would require major investment in mass transit within both counties.
 NOT RELEVANT  B. The majority of all vehicles on the nation’s freeways are traveling from one state to another.
 This shows that at least 60% of the commuters everyday are dailing commuters and there is a possibility that these people will ride the train.  C. 60% of the cars on Freeway Z are driven by people who live in County Y and work in County X.
 Again, not relevant  D. Many new freeways are being built in areas that are presently served by commuter trains.
 No connection to the question  E. A large proportion of the vehicles on Freeway Z are commercial trucks carrying transcontinental shipments.

ENAFEX · Answer

Option C is the correct answer but I am really struggling to accept this. Option C says  "60% of the Cars on the Freeway....."  The freeway could have had cars, trucks, buses..etc. Out of which only 60% of the cars are mentioned in this choice. Also the total number of cars could be as low as 2 or 3 cars as opposed to 2000 or 3000 trucks and buses.
So shouldn't I eliminate C?

kraizada84 · Answer

basically C states the proportion 60% on the road are most frequent travelers as they have their job in other state hence they will for sure commute the maximum and hence this lays stress on the conclusion that the number of cars clogging will be reduced.

hence C is the best choice over here.

HTH

mohnish104 · Answer

I think this is where the problem lies. In some CR questions you really have to twist your mind out of the way to come up with an answer. In this case, although a lot of you say E is "irrelevant", I don't think it is irrelevant. It might not be a strong contender. I don't know if many of you are aware of the concept of Goods Trains. If a large proportion of the vehicles on the highway are trucks trucks carrying those shipments then it would definitely benefit to take those trucks off the roads and put the shipments they carry on the trains thereby getting rid of the large proportion of traffic. If C wasn't mentioned E would have been the answer.

CintaThomas · Answer

what needs to be strengthened here?
it is: building tunnel would reduce cost & traffic congestion

A: weakens rather
B: not relevant, neither strengthens nor weakens
C: makes sense; BEST CHOICE
D: not relevant
E: not relevant

dhairya18 · Answer

CONCLUSION: Building a commuter train tunnel through the mountain range is a cost-effective solution to the traffic congestion on Freeway Z.

LINE OF REASONING:
Cause-Effect: Building a Commuter Train Tunnel -> Reduces the Number of Cars Clogging Freeway Z
Comparison: Train Tunnel Strategy = The Most Effective Option to Displace Freeway Z Drivers

CORE ASSUMPTION: The traffic on Freeway Z is primarily made up of local daily commuters who can actually use a passenger commuter train, rather than transcontinental travelers or commercial shipping trucks.

STRENGTHENING APPROACH: Provide evidence confirming that the traffic on the freeway is caused by local cross-county workers, validating the use of a commuter rail link.

OPTION ANALYSIS:
(A) Incorrect. This highlights a massive hidden expense (requiring major local mass transit investment), which undermines the claim that the plan is highly cost-effective.
(B) Incorrect. General national statistics provide no useful information about the specific traffic profile of Freeway Z. Infact it weaken the argument since If most drivers on the freeways are taking long-distance, interstate trips (traveling thousands of miles across different states), they are just passing through these two local counties. Long-distance travelers driving across the country are not going to pull over, park their cars, and get on a local 20-mile commuter passenger train.
(C) Correct. This supports the causal link. If 60% of the vehicles on the freeway are daily local commuters moving between the two targeted counties, a commuter train is perfectly suited to absorb this traffic and reduce congestion.
(D) Incorrect. This suggests that train systems are often insufficient to handle traffic demand on their own, which casts doubt on the soundness of the proponents' plan.
(E) Incorrect. If the traffic consists largely of transcontinental commercial cargo trucks, a local commuter passenger train will be useless at reducing the congestion, severely weakening the argument.

There is only one major road, Freeway Z, that links County X and Count

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There is only one major road, Freeway Z, that links County X and Count

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