Logical ReasoningDifficulty: Hard

PT10 S1 Q24 Explanation

The body of anyone infected

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

TopicsMust be True

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Stimulus

The body of anyone infected by virus X will, after a week, produce antibodies to fight the virus; the antibodies will increase in number for the next year or so. There is now a test that reliably indicates how many antibodies are present in a person’s body. If positive, this test can within a month how long that person has had the virus.

What this question is testing

Must be True

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
24.

Which one of the following conclusions is best supported by the

Answer choices

  1. Trap10% picked this

    Antibodies increase in number only until they have defeated

  2. Trap8% picked this

    Without the test for antibodies, there is no way of establishing whether a person

  3. Trap8% picked this

    Antibodies are produced only for viral infections that cannot be fought by any

  4. Trap14% picked this

    If a person remains infected by virus X indefinitely, there is no limit to the number of antibodies that can be

  5. Correct60% picked this

    Anyone infected by virus X will for a time fail to exhibit infection if tested

    Why this is right

    Answer E is correct.

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

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