For years the beautiful Renaissance buildings in Palitito have been da

For years the beautiful Renaissance buildings in Palitito have been damaged by exhaust from the many tour buses that come to the city. There has been little parking space, so most buses have idled at the curb during each stop on their tour, and idling produces as much exhaust as driving. The city has now provided parking that accommodates a third of the tour buses, so damage to Palitito's buildings from the buses' exhaust will diminish significantly.

Which of the following, if true, most strongly supports the argument?


(A) The exhaust from Palitito's few automobiles is not a significant threat to Palitito's buildings.

(B) Palitito's Renaissance buildings are not threatened by pollution other than engine exhaust.

(C) Tour buses typically spend less than one-quarter of the time they are in Palitito transporting passengers from one site to another.

(D) More tourists come to Palitito by tour bus than by any other single means of transportation.

(E) Some of the tour buses that are unable to find parking drive around Palitito while their passengers are visiting a site.


The question stem asks us to strengthen the argument.

Let’s take a look at the stimulus given-

Premises-
Renaissance buildings have long been damaged by the exhaust from tour buses that come to the city
Because there has been little parking space, most buses idle at the curb.
Idling (keeping the engines running) produces as much exhaust as driving
The city has now provided parking that accommodates a third of the tour buses

Conclusion-
damage to Palitito's buildings from the buses' exhaust will diminish significantly.

We need to find an option that strengthens the conclusion that by providing parking that accommodates a third of the tour buses, we will be able to reduce the damage to Palitito's buildings from the buses' exhaust significantly.


Let’s take a look at the options

(A) The exhaust from Palitito's few automobiles is not a significant threat to Palitito's buildings.

If the exhaust from automobiles is not a threat, how will providing parking space reduce the damage caused by the exhaust? Also, we are not talking about exhaust from few automobiles, but the exhaust from tour buses. If anything, option A weakens the argument. Eliminate.

(B) Palitito's Renaissance buildings are not threatened by pollution other than engine exhaust.

The scope of the argument is pollution/exhaust caused by tour buses. Pollution other than engine exhaust is out of the scope of the argument. Eliminate.

(C) Tour buses typically spend less than one-quarter of the time they are in Palitito transporting passengers from one site to another.
If tour buses typically spend less than one-quarter (25%) of the time they are in Palitito transporting passengers from one site to another, the rest of the time (75%), they are either idled at the curb or parked. If we provide parking that will reduce the exhaust from the buses that would otherwise idle at the curb. This will significantly diminish the damage caused by exhaust produced by the vehicles. Strengthens the argument. Correct.

(D) More tourists come to Palitito by tour bus than by any other single means of transportation.
Not relevant. If anything, option D weakens the argument. Eliminate.

(E) Some of the tour buses that are unable to find parking drive around Palitito while their passengers are visiting a site.
“Some” is a vague indicator. If they are unable to find parking space, they drive around. But the parking accommodates a third of the buses. This will reduce the exhaust significantly. The rest of the buses driving around does not strengthen the argument. Eliminate.



VP
GMAT SME

GMAT™ Official Guide 2020, Diagnostic Test, Critical Reasoning, Page 34, Question 80.

Key points: The question follows a strengthen-the-argument format. Look for any flaws to see what needs shoring up.
Breakdown:

1) The flip-side to the previous question, this straightforward question asks about what supports the argument. To do that, we need to understand the argument being made.

2) The passage informs us that exhaust from idling tour buses is damaging “beautiful Renaissance buildings.” To address the problem, the city has designated parking for buses, an action that “accommodates a third of the tour buses.” The argument is that because of the new parking arrangement, the damage “from the buses’ exhaust will diminish significantly.” What would help strengthen such an argument? Perhaps if we knew the buses that produced the most damaging exhaust (or the largest amount of it) were the ones using the dedicated spaces, that would help, or if the bus drivers were also no longer allowed to leave their vehicles idling. That is enough to get things going and turn to the answers.

Answers:

(A) automobile exhaust is not a significant threat

Analysis: This does touch on the environmental burden that buses in particular pose to the Renaissance buildings; on the other hand, it ignores the fact that two-thirds of the buses have no designated parking spaces, meaning that the majority of the most problematic polluters have NOT been removed. That certainly diminishes the impact of what otherwise appears to be a reasonable answer. Yellow light.

(B) the buildings are not threatened by other types of pollution

Analysis: This response introduces a consideration I had overlooked, namely that of other sources of pollution besides vehicles. As I said in the previous analysis, however, the fact that the new parking spaces accommodate just a third of the tour buses is problematic, and it is unclear what effect such a half measure (or less) will produce. This answer does not address the main problem that lies with the buses. With that said, I would go back and change my read on choice (A) to match this one: red light.

(C) Tour buses spend less than one-quarter of the time… transporting passengers

Analysis: If, as the passage states, “idling produces as much exhaust as driving,” then whether the tour buses are moving or not, exhaust can be an issue. But then the numbers come in: less than 25 percent of the time, the buses are shuttling people around, so more than 75 percent of the time, they are not. What about idling? With the new parking accommodations, one-third of the tour buses are presumably parked, or not idling, when immobile. It may not be a perfect solution, but it is better than anything else we have encountered up to this point. Yellow light.

(D) More tourists come… by tour bus

Analysis: I should sound like a broken record by now: the problem of exhaust from idling buses is not considered. Why would the passage go to such lengths to ensure that the reader understood the issue if it were not significant? Red light.

(E) Some… buses that are unable to find parking drive around

Analysis: Driving, like idling, produces exhaust, so only the parked buses would not be contributing to the overall pollution. Furthermore, what are we to make of “some”? That presumably means that some other buses that are unable to find parking do NOT drive around, which means that they idle. If the engine is on, the vehicle is doing harm. Red light.

Guessing: Choice (C) appears to be the best answer, despite being sub-optimal, in my mind. (A) is off-topic, focusing on another type of vehicle, while (D) distracts the reader with tourists. Among (B), (C), and (E), choice (E) hides behind a vague “some” and outright tells us that the buses “drive around,” which we know is comparable to idling, in terms of producing damaging exhaust. That leaves a 50/50 between (B) and (C), and only (C) sets restrictions on tour buses in particular. On these harder questions, if you had to put a finger on the subject of each answer and assess all of them from such a starting point, it might help you cut out some of the distractions. Look at what happens here, for instance:

(A) automobiles
(B) buildings
(C) buses
(D) tourists
(E) buses

From the time “buses” are mentioned in the first sentence of the passage, they remain the focus thereafter. It makes sense, then, that an argument that also stems from buses would need support in the form of--what else?--buses. Between (C) and (E), it is much easier to expose flaws in the latter.

Good luck with your studies.

- Andrew

IMO between B/C/D. Not sure how to reson among these. IMO C

Good question.

A. out of scope of the passage
E. even if 2/3 that cannot find parking just drive aroudn the city the pollution will increase
C. If the buses are spending only 1/4 of their time transporting tourists and are idiling 3/4 of the time on curbs emitting fumes then this will increase the pollution. However, if they can park in a parking lot and shut off the engines then pollution will at lest be reduced.

OA is C.

c) Tour buses typically spend less than one-quarter of the time they are in Palitito transporting passengers from one site to another.

This option states that its only 1/4 th of the time do the tour buses actually transport tourists.
The rest of the 3/4th time they are either idle or looking for parking space.
Therefore is directly strengthens the argument.

Option E on the other hand is close but says SOME which makes it less preferable over option C.

(A) The exhaust from Palitito's few automobiles is not a significant threat to Palitito's buildings.
but the exhaust specially during idling* is causing the damage-incorrect
(B) Palitito's Renaissance buildings are not threatened by pollution other than engine exhaust.
may or may not be in real but here , pollution other than engine exhaust is not under consideration-incorrect
(C) Tour buses typically spend less than one-quarter of the time they are in Palitito transporting passengers from one site to another.
True, because so much time idling can cause enough pollution to damage the buildings-correct
(D) More tourists come to Palitito by tour bus than by any other single means of transportation.
may or may not be in real, but here , any conveyance other than the tour buses is not under consideration-incorrect
(E) Some of the tour buses that are unable to find parking drive around Palitito while their passengers are visiting a site.
they can roam around and park the vehicle to some distance place, and can avoid idling -incorrect

*idling is a state of vehicle when the engine is running but the vehicle is idle and standing , when we see a red light on traffic signal we standby the vehicle without switching off the engine.

The statement does not indicate that there is MORE exaust gas emitted when idling compared to that when it is in running state. Which means that irrespective how much time the bus spends idling Vs time spent on running is irrelevent. But the fact that other automobiles do not pollute as much as the buses do ,, would mean that when the bus pollution issue is addressed we are going to see a substantial decrease in pollution of the buildings.

Where am I going wrong ?

Hi ramanujanu:

Maybe my post helps you.

You're correct: The statement does not indicate that there is MORE exaust gas emitted when idling compared to that when it is in running state.

Actually, you don't need that information at all. The fact that idling vehicles create MORE or LESS exhaust does not matter.

The proposal is based on the assumption that idling vehicles DO emit exhaust.
There are two types of vehicles: (1) running; (2) idling.
You cannot anything to affect running vehicles. The only thing you can do to reduce exhaust is STOP idling vehicles emitting. Correct?

How do you make idling vehicles STOP emitting ==> The solution is building parking garage. Those vehicle will stop emitting when they are parked.

Let get back to answer C. why C is correct.

C says: "Tour buses spend less than 1/4 of the time they are transporting passengers from one site to another." It means these tour buses spend almost the time on IDLING. That's KEY point for the success of the proposal. Because if these buses run almost the time. You cannot do anything to stop them emitting exhaust.

Hope my post helps.

So let's start by quickly putting into easy words what this whole situation is about. So we have some city where buses are ruining the buildings. Most buses pretty much do 2 things- they either drive passengers around or they idle around doing nothing. In either case, buildings are damaged by the exhaust. So the city thinks building parking that will accommodate 1/3 of buses will lessen exhaust damage. Now let's look at the answer choices.

A) Who cares about regular automobiles? We are only concerned about buses and parking spots here. It's a trap choice because the GMAT is trying to shift your thinking towards alternative causes of pollution; a type of thinking handy on many other CR questions. If we can assume other things won't make the problem worse, we would have reason to believe this plan might work, but this is exactly the type of thinking the GMAT is tricking you with here, since the prompt says the buildings are damaged by buses, and thus cars don't matter here.

B) Whether other pollution harms these buildings or not does not matter as well, since the plan seeks to reduce damage from buses and not other sources. Pretty easy one to eliminate.

D) Also may be a trap answer for some test-takers. D confirms the idea that buses constitute the majority proportion of tourist traffic. Either way, this does not support the city's plan that parking will reduce bus pollution. Whether buses are 99% of all tourist traffic or 51%, this has no bearing on the fact that additional parking will reduce current pollution levels.

E) Okay, this is probably the trickiest and most appealing trap answer choice here. Here's why it's a trap- E states that some of the buses that can't find parking are gonna just drive around polluting the city with reckless abandon, so you think great, additional parking will definitely reduce pollution because these buses would be parked instead of driving around. But here's the thing, what would those buses that can't find parking do instead? They are either going to idle around, polluting the city anyway. E doesn't actually change anything about what we already know of this world. E is in fact, describing a scenario that is, in terms of pollution output, fundamentally the same as what is already written in the prompt. We already know parking is limited, and that buses idle around because of this. Whether they drive around or idle around makes no difference to the level of harm the buildings will experience. So it doesn't really support the plan, E is rather neutral.

C) THE CORRECT ANSWER! Whew, we made it guys! Let's look at why C definitely is the correct answer. C says buses spend less than one-quarter of the time transporting people around from site to site. So the rest of the time, the MAJORITY of the time, these buses need to find somewhere to park or they will just idle around. The prompt says parking is limited though, so most of the time these buses are damaging buildings by idling at the curb. If a third of these buses are now able to find parking, you'd have good reason to believe the pollution to buildings will decrease, thereby strengthening the logic of the prompt. It is also important to note that C says the majority of the time is spent idling, since parking is the alternative to idling; thus, buses will actually spend a lot of time parked and therefore not polluting.

Isn't "most strongly support"..type questions inference questions? That is, the correct answer must be "derived" from the argument in the stimulus?
Although I see how C could be the correct answer, from the available options, how is C "derived" from the argument?

There's an easier way.

ANY question starting with either of these——
Which of the following, if true, ...
Which of the following would be useful/important/etc...
——is asking for NEW INFORMATION that would impact the argument.

Note
"if true"
"would"
These words—or some equivalent—MUST appear in the question, because you DO NOT (and CANNOT) "prove" these statements. The whole point is that they're completely new outside hypotheticals.

Ordinary conversation is no different.
"If you found out xxxxx, what would you think about me?" —> "xxxxx" is a totally random outside thought, but, the point is to consider what would happen if it were actually true. (It should be plain that "xxxxx" is not something you could "support" or "prove"; it's a random hypothetical.)

__

Problems about "inferences", on the other hand, could ABSOLUTELY NEVER possibly contain either of the wordings above.

If this isn't perfectly clear, then, think about it for a bit.

Hi,

Can someone explain what category of questions does this argument fall under?

^^ "Which of the following, if true, most strongly supports the argument?" ...so it's a strengthening question

E is still not clear.
So many explanations already but if some buses which do not get parking drive around, if they get parking they wont drive around and reduce the damage.
Are we saying that driving around doesn't cause exhaust near the building so this is not our target set of buses?

Hello, rk0510. No one is saying that "driving around doesn't cause exhaust near the building." In fact, driving produces exhaust, plain and simple, and that damages the Renaissance buildings of Palitito. The issue that must be addressed is reducing exhaust by tour buses, and choice (E) does not achieve that. Again, whether idling or driving around, tour buses produce exhaust that damages the buildings. Only buses with their engines turned off will help reduce the pollution, and only choice (C) touches on this point in any notable way.

I would be happy to discuss the point further if you need clarification.

- Andrew

So exhaust from the idling produces as much exhaust as driving. So Parking space will be beneficial only when buses park in Engine Off Mode I believe. Point to be noted is that we only have parking for 1 out of every 3 buses. Not the best but better than 0 out of 3.



Let's make sure Parking spaces are actually helping



Well, we kind of already know it is a threat. And we really don't have a concern for few automobiles. We are looking for really specific. Tourist buses. So Out Of Focus.



Well, that's a great news but has nothing to do with how Parking spaces will help exhaust coming from those buses.



What does it say. Out of 60 minutes, the bus is in transit (Engine On = Exhaust) for less than 15 minutes. So that means for 45 minutes the bus is idle if it doesn't have the parking space to turn the engine off. So now at least 1 bus out of every 3 buses will be parked with Engine off for 45 minutes. That sounds good to me. The plan will have a good impact.



Sure. We have more buses than trains/cycles/planes. But what will parking has to do with it? Let's say 75% people come by bus and 25% by cars. So? What can you infer about parking spaces being available to buses.



I guess that's same as idling. Bus is idling or driving creates the same exhausts. So it is like no new information to me.

Hi AndrewN,

I feel everyone is trying to avoid the main question being posed by option E, and just driving the debate towards idling and driving. What we really want to know is, that if at the moment, some buses are driving around because of lack of parking space, then wouldn't building of new parking spaces help, as these buses will be able to park themselves there with engines turned off ?