Last time, I covered in detail how to approach weaken the conclusion question in GMAT critical reasoning. Today, I’d like to cover another very common CR question type – strengthen the conclusion. It’s important to remember that the proper identification of the question is half the battle because the question type will dictate how we analyze the argument. Strengthen the conclusion questions can be found in a variety of different forms:

Common forms of this question are:

• Which of the following, if true, most strongly supports…
• Which of the following, if true, provides most support for…
• Which of the following, if true, would most strengthen…
• Which of the following, if true, most significantly strengthens…

What to look for

Strengthen the conclusion questions are almost exactly identical to weaken the conclusion questions. The key difference is that instead of weakening the argument, we are looking for methods to support the main idea. Strengthening the main idea can be accomplished by:

1. Introducing additional evidence to fix any potential weaknesses in conclusion logic
2. Introducing supporting information to support the writer’s logic.

Example

The earth’s resources are being depleted much too fast. To correct this, the United States must keep its resource consumption at present levels for many years to come.

Which of the following, if true, would most strengthen the argument above?

1. New resource deposits are constantly being discovered.
2. The United States consumes one-third of all resources used in the world.
3. Other countries need economic development more than the United States does.
4. Other countries have agreed to hold their resource consumption at present levels.
5. The United States has been conserving resources for several years.

The Diagram

1E        Earths resources deplete too fast
2C        USA keep consumption at present level for years

Explanation

Looking through the answer choices, A, C, E can immediately be eliminated. The language in these choices is completely outside the scope of the question and passage. Between B and D, we are looking for information that can support the conclusion. Answer D does not provide support for the conclusion because other county’s resource consumption has nothing to do with the fact that the United States must keep resource consumption at current levels. Answer B, the fact that the United States consumes one third of all resources used in the world supports the conclusion. The logic behind this is that the United States cannot increase consumption to more than one third of the world’s resources or they risk depleting the earth’s resources even faster. The correct answer is B.

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