A GMAT Strengthen Trap: A Better Alternative Doesn't Mean the Plan Fails

A GMAT Strengthen answer choice can offer a genuinely better alternative to a plan and still fail to support the conclusion that the plan will not work. This post breaks down the Better-Alternative Trap using an Official GMAT question on airport delays, and the exact check that separates "the plan is not the best option" from "the plan does not work."

This GMAT Critical Reasoning Strengthen question opens, "Only a reduction of 10 percent in the number of scheduled flights using Greentown's airport will allow the delays that are so common there to be avoided," and it turns on how precisely you read the conclusion before you weigh a tempting alternative.

Here is a trap that turns entirely on how carefully you read the conclusion. A choice presents a better alternative to the plan, and a better alternative feels like it bears on the plan. However, whether it does depends completely on what the conclusion actually claims.

Here is the idea. Suppose an argument concludes that a particular plan will not produce a certain result. You are asked to support that conclusion. Now a choice tells you that a different option would be better, or more attractive, than the plan. Does that support the conclusion? It does not. "This plan does not produce the result" and "this plan is not the best option" are two different claims. A better alternative existing speaks to the second. It says nothing about the first. Whether something else is more attractive does not tell you whether this plan delivers the result in question.

The question setup

Greentown airport suffers from chronic delays, and avoiding them would require cutting its scheduled flights by 10 percent. A nearby airstrip, Hevelia, could be upgraded into a full-service airport, and if it were, it can draw away a share of Greentown's passengers. The conclusion is the experts' position: even after Hevelia is turned into a full-service airport, the chronic delays at Greentown would not end. You are asked to justify that position, which means strengthening the claim that the conversion would not end the delays.

Read the conclusion precisely, because the whole choice rides on it. The experts' claim is about a result: turning Hevelia into a full-service airport would not end the delays. It is not a claim about how Hevelia ranks against other options. It does not say Hevelia is the only possible fix, or the best one, or that no other airstrip could do better. It says this particular conversion would not deliver the result.

The Better-Alternative Trap

Now consider answer choice B, which says that another largely undeveloped airstrip, closer to Greentown than Hevelia, would be a more attractive alternative for many passengers who currently use Greentown.

Choice B offers a better option than Hevelia, a closer airstrip that more passengers would prefer. To a student reading the experts loosely as doubting Hevelia, that can feel like support: if something else is more attractive, maybe Hevelia is not the answer. But notice what that reasoning has quietly done. It has slid from "Hevelia would not end the delays" to "Hevelia is not the best option," and treated evidence for the second as if it supported the first.

Look at what the conclusion actually claimed. It said the Hevelia conversion would not end the delays. Whether some other airstrip would be even more attractive has no bearing on that. A closer, more appealing alternative existing does not tell you that the Hevelia conversion fails to end Greentown's delays. Both could be true: Hevelia might end the delays, and the other airstrip might be more attractive still. A more attractive option does not make the original plan ineffective. So Choice B leaves your belief in the experts' conclusion exactly where it was.

Here is the point worth holding onto, and it is about when a better alternative actually matters. It comes down to what the conclusion claims:

• If the conclusion is about whether the plan produces a result, a better alternative is irrelevant. Something else being superior does not stop the plan from producing the result.
• If the conclusion is that the plan is not the best option, a better alternative is exactly what supports it. A superior option existing is precisely what "not the best" means.

The experts' conclusion here is the first kind. It says the Hevelia conversion would not end the delays, a claim about whether the plan produces a result, not a claim about how Hevelia ranks against other options. That is why a more attractive airstrip does nothing for it.

The correct answer

The correct choice says that several airlines use Greentown as a regional hub, so most flights landing there carry many passengers who then catch connecting flights onward to their final destinations. This one does the work. If many of Greentown's passengers are only connecting through it, they have a reason to keep using Greentown rather than switch to Hevelia, since switching would force them to travel to Hevelia and then back to Greentown for the connection. That makes it more believable that the converted Hevelia would not pull enough traffic away to end the delays. It bears directly on the actual conclusion, whether this conversion ends the delays, rather than on whether some other option is more attractive.

The habit this builds

The discipline this question builds is to fix the exact wording of the conclusion before you weigh any choice that offers an alternative. Ask whether the conclusion is about whether the plan produces a result or about how it ranks against other options. A better alternative is decisive for the second and irrelevant to the first, and the only way to know which you are dealing with is to have read the conclusion precisely rather than approximately.

Series context

This question is part of the Strengthen Beginner Series, in which easy Official GMAT questions are used not to test what you know, but to reveal how you think. Each question targets a specific reasoning habit, one that shows up in a simple form on easy questions and a complex one on hard questions. If you are getting started with Strengthen questions or if Strengthen questions feel inconsistent for you, this series is built to show you exactly where the process is breaking down.

Solve the question on your own first. The reasoning you apply matters more than the answer you reach.

Read about other Strengthen Traps and Tips:

1. One Habit That Changes How You Solve Strengthen Questions
2. Trap #1 - Additional Benefit
3. Trap #2 - Two-Way Answer
4. Trap #3 - Choice Supporting Premise
5. Trap #4 - Implementation Of Plan
6. Trap #6 - Not Action Trap

Take a free diagnostic quiz to see how your own process holds up on questions like this one.