Logical ReasoningDifficulty: Hard

PT126 S3 Q22 Explanation

In a study, one group of volunteers

A free, expert breakdown of this official LSAT Logical Reasoning question.

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Stimulus

In a study, one group of volunteers was fed a high­-protein, low-carbohydrate diet; another group was fed a low-protein, high-carbohydrate diet. Both diets contained the same number of calories, and each volunteer's diet prior to the experiment had contained moderate levels of proteins and carbohydrates. After ten days, those on the low­-carbohydrate to lose body fat is to eat much protein and shun carbohydrates.

What this question is testing

Weaken

Your task

Find the choice that makes the argument's conclusion less likely to be true.

Common trap

Answers that look negative but attack a claim the argument never relied on.

Winning move

Find the assumption the argument depends on, then pick the choice that undermines it.

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The question
22.

Which one of the following, if true, most weakens the

Answer choices

  1. Correct64% picked this

    A low-protein, high-carbohydrate diet causes the human body to retain water, the added weight of which largely compensates for the weight of any body

    Why this is right

    This points to the term shift in the argument’s conclusion and changes the results of the study. It suggests that those on the high-carbohydrate diet might have lost more body fat than was initially indicated. How much more though is unclear. But if it’s more than the low-carbohydrate diet, the argument’s conclusion would be false.

    Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.

  2. Too Weak17% picked this

    Many people who consume large quantities of protein nevertheless gain significant amounts

    Without knowing that these people shunned carbohydrates or that they refrained from eating absurd amounts of food, they are not a relevant counter example.

  3. Strengthen9% picked this

    A high-protein, low-carbohydrate diet will often enable the human body to convert some body fat into muscle, without causing

    This makes the conclusion more likely to be true by providing a further unknown amount of body fat that could be lost in addition to that lost from weight loss.

  4. Strengthen6% picked this

    In the experiment, the volunteers on the high­-carbohydrate diet engaged in regular exercise of a kind known to produce weight loss, and those

    This suggests the weight loss by the high-carbohydrate diet cannot all be attributed to the diet, making the amount of weight loss attributable to the diet something less than was appreciated before. This makes it more likely that a low-carbohydrate diet is the most effective way to lose body fat.

  5. Out of Scope4% picked this

    Many of the volunteers who had been on the low-carbohydrate diet eventually regained much of the weight they had lost on the diet

    What happens after one loses weight is not relevant when determining the most effective way to lose body fat in the first place.

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