Logical ReasoningDifficulty: Easy

PT3 S2 Q21 Explanation

The public is well aware that

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

TopicsNecessary Assumption

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Stimulus

The public is well aware that high blood cholesterol levels raise the risk of stroke caused by blood clots. But a recent report concludes that people with low blood cholesterol levels are at increased risk of the other lethal type of stroke—cerebral hemorrhage, caused when a brain artery bursts. The report suggests by Japanese researchers that Western diets better protect against cerebral hemorrhage than do non-Western diets.

What this question is testing

Necessary Assumption

Your task

Find the assumption the argument requires in order for its conclusion to hold.

Common trap

Answers that would help the argument but aren't strictly required (sufficient, not necessary).

Winning move

Negate each choice — the right one breaks the argument when negated.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
21.

The argument is based on which one of the

Answer choices

  1. Trap3% picked this

    Western diets are healthier than non-Western

  2. Correct85% picked this

    Western diets result in higher blood cholesterol levels than do

    Why this is right

    Answer B is correct.

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

  3. Trap5% picked this

    High blood cholesterol levels preclude the weakening of

  4. Trap2% picked this

    Cerebral hemorrhages are more dangerous than strokes caused by

  5. Trap5% picked this

    People who have low blood pressure are at increased risk of

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