Logical Reasoning

PT102 · S2 · Q12 It has long been thought that lizards

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It has long been thought that lizards evolved from a group of amphibians called anthracosaurs, no fossils of which have been found in any rocks older than 300 million years.

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.

12.

An assumption made in the argument is that there are no

  1. Correct

    unknown anthracosaur fossils older than

    Why this is right

    Answer A is correct.

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

    77% picked this

  2. unknown lizard fossils older than

    Trap

    2% picked this

  3. known lizard fossils that predate

    Trap

    5% picked this

  4. known anthracosaur fossils that predate

    Trap

    16% picked this

  5. known lizard fossils whose age

    Trap

    0% picked this

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