Logical ReasoningDifficulty: Medium

PT107 S1 Q10 Explanation

The symptoms of hepatitis A appear

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

TopicsParadox

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Full official LSAT questions are available through LawHub. This page provides LSAT Lab's explanation, strategy, and review tools without republishing the full official question.

Stimulus

The symptoms of hepatitis A appear no earlier than 60 days after a person has been infected. In a test of a hepatitis A vaccine, 50 people received the vaccine and 50 people received a harmless placebo. Although some people from each group eventually exhibited symptoms of hepatitis A, effective in preventing infection with the hepatitis A virus.

What this question is testing

Paradox

Your task

Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.

Common trap

Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.

Winning move

Predict what a right answer must do, then test each choice against the conclusion-evidence gap.

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

The question
10.

Which one of the following, if true, most helps resolve the apparent discrepancy in

Answer choices

  1. Trap2% picked this

    The placebo did not produce any side effects that resembled any of the symptoms

  2. Trap4% picked this

    More members of the group that had received the placebo recognized their symptoms as symptoms of hepatitis A than did members of the

  3. Trap2% picked this

    The people who received the placebo were in better overall physical condition than were the people

  4. Correct78% picked this

    The vaccinated people who exhibited symptoms of hepatitis A were infected with the hepatitis A

    Why this is right

    Answer D is correct.

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

  5. Trap13% picked this

    Of the people who developed symptoms of hepatitis A, those who received the vaccine recovered more quickly, on average,

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