Logical ReasoningDifficulty: Easy

PT126 S4 Q14 Explanation

In 1963, a young macaque

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

TopicsNecessary Assumption

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Stimulus

In 1963, a young macaque monkey was observed venturing into a hot spring to retrieve food which had fallen in. Soon, other macaques began to enter the spring, and over a few years this behavior was adopted by the entire troop. Prior to 1963, no macaques had ever been observed in the new patterns of social behavior, and are not complete captives of their genetic heritage.

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
14.

Which one of the following is an assumption required by the

Answer choices

  1. Trap2% picked this

    Mutations in the genetic heritage of a certain variety of macaques can occur over a time span as short as

  2. Correct84% picked this

    New patterns of behavior that emerge in macaque populations over the course of a few years or decades

    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. Trap1% picked this

    Only when behaviors become typical among an animal population can we conclude that a genetic alteration has occurred

  4. Trap12% picked this

    The social behaviors of macaques are completely independent of their

  5. Trap1% picked this

    The macaques’ new pattern of behavior will persist over

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