Automobile emissions are a significant source of air pollutants, and

See, the question is, which one says that both of the aims will be not be achieved. So we need to look for the choice that will undermine one of them. Here again we see the importance of reading the question very carefully.

We see that E only does that and none of the other undermines even one of the aims.

Its clearly asked in the question that we have to undermine both.....hence there cannot be any compromise with undermining just one.
I think C undermines best as it says there was no export hence a potential foreign country market remains unexploited which leads to weakening in terms of economics.
Second Its clearly stated that even the new cars also cause pollution and hence there is no reason to think that these new cars which will be sold only in the home county will not spread pollution.
Hence i think option C finds a mid way pathway to weaken both. we must not forget an option need not weaken 100% .....
E IMO cannot be an option as it is specifically mentioned in the question that we have to weaken both the aims not just. We cannot rephrase the question as we like.

Dear Archit143,

Tell me what does the following mean?

It is not likely that both of the aims will be met.

Hi
Its clear enough "It is not likely that both of the aims will be met...".
Moreover the question asks to select an option that weaken both aims of the plan.....

The aims are to boost Torinia's economy and reduce air pollution.

In the question you will find the words undermines the likelihood that both of the aims will be met which means it is not likely that both of the aims will be met. In other it is likely that only one of the aims will be met.

I understand the source of confusion. Consider the sentence: It is likely that he understands both English and French, and consider the sentence: It is not likely he understands both English and French.

Does not the second sentence imply that he probably understands only one of them?

In general when you negate something that refers to two things or persons, you imply that only one of them is referred to.

Which of the following, if true, most seriously undermines the likelihood that the planned incentives, if implemented, will achieve both of the cited aims?
The question stem states which of the following will show that if planned incentive is implemented both the cited aims will be met.....Even if neglect the if part it comes out to be Which of the following will weaken the planned incentive to achieve both of its goals.
How can than we rephrase from our comfort and say it just says to weaken one of the goal

Ok, I will keep it simple. What does "not both" mean?

Does it mean:

(1) neither
or
(2) only one of them

Also to mean "none of the two aims will be achieved" , we use neither of the two and not both.

Conclusion- Replacing and scrapping old cars will reduce air pollution.
We have to weaken this conclusion .

(A) Without the implementation of the planned incentives, most Torinians who own an old car would be unlikely to buy a new car. What about effects on pollution?
(B) Torinia's automobile plant manufactures car models that typically generate smaller amounts of air pollutants than most similarly sized car models manufactured elsewhere. We are not concerned about cars anywhere else.
(C) The new cars produced in Torinia are not likely to be exported to other countries. What about pollution? The cars are not exported out implies that people will buy the cars and scrap old cars? This strengths the argument instead of weakening if people will buy and use the new cars.
(D) The largest source of atmospheric pollutants in Torinia is not automobile emissions, but emissions from power plants. But, using new cars will reduce pollution by at least small percentage.
(E) The manufacture and the scrapping of cars each generate significant amounts of air pollutants. If scrapping generates significant pollution, then there is no pint using new cars

Stem: Find an answer which undermines the likelihood that "economy boost" and "less pollution" cannot be achieved using incentives.


Premises:

1. Automobile emissions are a significant source of air pollutants
2. cars over five years old typically generate significantly greater amounts of pollutants than newer cars
3. Torinia has recently built its first automobile manufacturing plant
4. Most cars in Torinia are over five years.

Using these premises it can be concluded that if incentives are given then, old cars will be replaced, reducing pollution and since new cars are bought, the business of the manufacturing unbit will prosper and economy gets a boost.

So something has to be found out that will not lead to pollution reduction and economy boost. However, one thing should be remembered that economy factor is dependent on the buying of new cars which will take place only if the old cars are scrapped due to reason of pollution. Incentive will help buying of new cars which will reduce pollution and hence trigger the economy.


PoE:


(A) Without the implementation of the planned incentives, most Torinians who own an old car would be unlikely to buy a new car.

Out of Question. You have to find where the two benefits wont be achieved when incentives are used.

(B) Torinia's automobile plant manufactures car models that typically generate smaller amounts of air pollutants than most similarly sized car models manufactured elsewhere.

Thats good. It shall be a factor which shall reduce pollution and if incentives are there, people will buy and would boost the economy. But we are looking for a factor which shall undermine the likelihood that the two things can be achieved. This strengthens and not weakens the success of incentivizing.

(C) The new cars produced in Torinia are not likely to be exported to other countries.

How does it affect the success of incentivizing. If nothing better, it strengthens as most cars will be sold in Torinia after incentives.

(D) The largest source of atmospheric pollutants in Torinia is not automobile emissions, but emissions from power plants.

Let it be the largest. There is no comparison here. We want to reduce air pollution and elimination is not practically possible. This is out of scope as it does not emphasize what happens if incentives are given. However, premise say that it is significant contributor, largest or not does not matter.

(E) The manufacture and the scrapping of cars each generate significant amounts of air pollutants.

If this happens, the aim of lessening the air pollution wont be satisfied as significant amount of air pollution is caused in both old cars as well as manufacturing of new cars and scrapping of old cars. The argument states as premise that
"cars over five years old typically generate significantly greater amounts of pollutants than newer cars". But if the procedure in this transition leads to same amount of pollution, why will people even think of changing their cars even if there are incentives. They are not going to receive the cars for free. These are just incentives. Since government expects that people can help in reducing pollution, they provide incentives. And if new cars are not purchased then there is no point boost in economy.

Answer is E.

Both the aims should be achieved, but here one aim depends on other and hence the primary aim is reducing air pollution as supplemented by the premise. This is the most suitable option.

I chose D because air pollutants and atmospheric pollutants mean the same thing. Furthermore, E suggests manufacturing and scrapping each generate the same pollutants while D specifically states (more) manufacturing is worse than keeping the (current) automobiles.

In hindsight, I would choose E because it uses the exact word 'air' as opposed to atmospheric'.

Any thoughts on this?

i think its very low quality question because E clearly doesn't mention how economy would be impacted.
we have to find an answer that will achieve both of the aims.

very surprising its from official GMAT prep.

mrdlee23

Thankfully, we don't need to be content experts to answer this, so there's no need to deliberate on the difference between air pollution and atmospheric pollution. (As far as I can see, they are identical in this context, but we can't be expected to solve the problem on that basis.)

The issue with D is that it doesn't tell us whether buying new cars is good or bad. It's talking about power plants, which have nothing directly to do with the argument at all. Cars don't have to be the #1 source of pollution in order for us to help out by changing our habits, so it doesn't matter if something else causes more pollution than cars. And if you're imagining that D is talking specifically about the power used to make new cars, be careful--there's no mention at all of that. D is simply saying that if you add up all the electricity we generate in power plants for all purposes, that causes more pollution than auto emissions. That doesn't matter at all, since it doesn't tell us whether to get a new car or not.

E, on the other hand, brings up a disadvantage of the plan. If ditching your old car and buying a new one causes a lot of pollution, maybe you won't reduce pollution by trading in your old car. You might--we don't have the numbers--but all we have to do is weaken, not disprove. (By the way, this is true in real life. Those of us who are concerned about pollution should only buy a fancy new low-emissions car if we actually need a new car, or if our old car is truly disastrous! )

Power plant should not be out of scope. Read the aim carefully in the stimulus. It says the aims are 1. to reduce air pollution. 2. to improve the economy. If the main issue is Power plants, how will replacing cars help achieve either of these goals?