Ethanol, a fuel derived from corn, can be used alone to power vehicles

Question

Ethanol, a fuel derived from corn, can be used alone to power vehicles or along with gasoline to reduce the amount of gasoline consumed. Compared with conventional gasoline, pure ethanol produces significantly less pollution per gallon used. In order to combat pollution, many individuals advocate the increased usage of ethanol as a fuel source for vehicles in conjunction with or in place of gasoline.

In evaluating the recommendation to increase the use of ethanol, it would be most important to research which of the following?

(A) Whether the majority of existing vehicles are capable of using ethanol for fuel, either alone or in conjunction with gasoline 
(B) Whether the process of growing corn to produce ethanol results in significant amounts of pollution 
(C) Whether completely replacing gasoline with ethanol results in less pollution than using ethanol in conjunction with gasoline 
(D) Whether ethanol is more expensive to produce than conventional gasoline 
(E) Whether there are some vehicles in which using ethanol fuel would not result in a significant reduction in pollution compared to conventional gasoline

Aabhash777 · Answer

Premise: Ethanol (fuel derived from corn) when used in vehicles produces less pollution than vehicles powered by gasoline.

Conclusion: Use ethanol powered vehicle in conjunction with or in place of gasoline powered vehicles.

Here only two option choices seem feasible at first A and B.

Option A:
Whether the majority of existing vehicles are capable of using ethanol for fuel, either alone or in conjunction with gasoline

It doesn't matter if majority or even minority of vehicles are capable of using ethanol for fuel. Even if say 20% of vehicles are capable of using ethanol then pollution will be reduced. So this option is not the answer.

Option B:
 Whether the process of growing corn to produce ethanol results in significant amounts of pollution

This makes sense as say if producing ethanol creates more pollution than using it as fuel. the net pollution will be still higher.

Option B is the answer.

work2 · Answer

How are we eliminating option E? because the argument talks about using a cleaner fuel source

guddo · Answer

Ethanol, a fuel derived from corn, can be used alone to power vehicles or along with gasoline to reduce the amount of gasoline consumed. Compared with conventional gasoline, pure ethanol produces significantly less pollution per gallon used. In order to combat pollution, many individuals advocate the increased usage of ethanol as a fuel source for vehicles in conjunction with or in place of gasoline.
 
 In evaluating the recommendation to increase the use of ethanol, it would be most important to research which of the following?

The recommendation is to use more ethanol in order to reduce pollution.  The key issue  is whether ethanol reduces pollution overall, not just when it is burned in vehicles. Since ethanol comes from corn, we must consider whether  producing the corn for ethanol creates a lot of pollution .

(A) Whether the majority of existing vehicles are capable of using ethanol for fuel, either alone or in conjunction with gasoline

This matters for practicality, but it is not the most important issue for evaluating the pollution argument. Even if many vehicles can use ethanol, we still need to know whether ethanol reduces pollution overall.

(B) Whether the process of growing corn to produce ethanol results in significant amounts of pollution

This is correct. The argument compares pollution from burning ethanol with pollution from burning gasoline. But if growing corn for ethanol creates significant pollution, then increased ethanol use may not actually combat pollution overall.

(C) Whether completely replacing gasoline with ethanol results in less pollution than using ethanol in conjunction with gasoline

This compares two ethanol-use options. But the recommendation allows either using ethanol with gasoline or using it instead of gasoline. The bigger question is whether increased ethanol use reduces total pollution at all.

(D) Whether ethanol is more expensive to produce than conventional gasoline

This is about cost, not pollution. The recommendation is made in order to combat pollution, so price is not the central issue.

(E) Whether there are some vehicles in which using ethanol fuel would not result in a significant reduction in pollution compared to conventional gasoline

This is too limited. “Some vehicles” would not strongly evaluate the general recommendation. The broader issue is whether ethanol production itself creates significant pollution.

Answer: (B)

egmat · Answer

Hi work2,

You're right that the argument is about switching to a cleaner fuel, so it makes sense that E  feels  on-topic. Let me show you where it slips.

The key is the word  "some"  in E:  "whether there are  some  vehicles in which using ethanol fuel would not result in a significant reduction in pollution."

Think about how an  Evaluate  question works: the right answer is the one whose answer could swing the recommendation one way or the other. So test both directions of E:

-  Yes, some vehicles don't benefit.  Okay - but the recommendation is a  general  one to increase ethanol use. If a handful of vehicles see no gain while the rest do, the overall plan to combat pollution still stands.
-  No, all vehicles benefit.  This just confirms what the passage already grants.

Either way, the core recommendation barely moves. That's why E isn't "most important."

Compare that to  B . The passage only tells us ethanol is cleaner  "per gallon used"  - that's tailpipe pollution only. It says nothing about the pollution created while  growing the corn and producing  the ethanol. If that production is dirty, the whole point of switching collapses; if it's clean, the recommendation holds strong. B swings the conclusion hard - E doesn't.

Turn one knob to feel it:  what if E said  "the  majority  of vehicles"  instead of  "some" ? Now a "yes" would genuinely threaten a broad recommendation, and E would become much more relevant. With just  "some,"  it stays too narrow to matter.

That scope word is the whole difference here.

Answer: B

anshhh2705 · Answer

The problem with option E is that it is talking about some vehicles (let's assume 40%) which may not see a significant reduction in pollution as compared to gasoline. The amount of pollution might end up being a less significant reduction. The other 60% may see a significant reduction, hence supporting the argument.

work2

How are we eliminating option E? because the argument talks about using a cleaner fuel source

Ethanol, a fuel derived from corn, can be used alone to power vehicles

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Ethanol, a fuel derived from corn, can be used alone to power vehicles

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