Logical ReasoningDifficulty: Hard

PT5 S3 Q21 Explanation

Naturalist: For decades we have

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

TopicsPrinciple-Strengthen

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Stimulus

Naturalist: For decades we have known that the tuatara, a New Zealand reptile, have been approaching extinction on the South Island. But since South Island tuatara were thought to be of the same species as North Island tuatara there was no need to protect them. But new research indicates that the South obliged to prevent their extinction, even if it means killing many of their unendangered natural predators.

What this question is testing

Principle-Strengthen

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
21.

Which one of the following principles most helps to justify the

Answer choices

  1. Trap4% picked this

    In order to maximize the number of living things on Earth, steps should be taken to preserve all

  2. Trap2% picked this

    When an animal is in danger of dying, there is an obligation to help save its life, if doing so would not interfere with

  3. Correct67% picked this

    The threat of local extinction imposes no obligation to try to prevent that extinction, whereas the threat of global extinction

    Why this is right

    Answer C is correct.

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

  4. Trap2% picked this

    Human activities that either intentionally or unintentionally threaten the survival of an animal species ought

  5. Trap26% picked this

    Species that are found in only one circumscribed geographical region ought to be given more care and attention than are other species because

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