Logical Reasoning

PT105 · S1 · Q4 In an experiment testing whether

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In an experiment testing whether hyperactivity is due to a brain abnormality, the brain activity of 25 hyperactive adults was compared to the brain activity of 25 adults who were not hyperactive.

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.

4.

Which one of the following, if true, most undermines the conclusion drawn by the experimenters?

  1. Some of the nonhyperactive adults

    Trap

    0% picked this

  2. The hyperactive adults who participated

    Trap

    3% picked this

  3. The neuropsychologists who designed the

    Trap

    1% picked this

  4. Correct

    All of the hyperactive adults

    Why this is right

    Answer D is correct.

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

    95% picked this

  5. The test was performed only

    Trap

    1% picked this

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