Logical ReasoningDifficulty: Medium

PT1 S3 Q19 Explanation

Train service suffers when a railroad

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

TopicsNecessary Assumption

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Stimulus

Train service suffers when a railroad combines commuter and freight service. By dividing its attention between its freight and commuter customers, a railroad serves neither particularly well. Therefore, if a railroad is going to be a exclusively on one of these two markets.

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
19.

For the argument to be logically correct, it must make which of the of

Answer choices

  1. Trap9% picked this

    Commuter and freight service have little in common with

  2. Trap12% picked this

    The first priority of a railroad is to be a

  3. Correct69% picked this

    Unless a railroad serves its customers well, it will not be

    Why this is right

    Answer C is correct.

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

  4. Trap7% picked this

    If a railroad concentrates on commuter service, it will be a

  5. Trap3% picked this

    Railroad commuters rarely want freight service

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