Logical ReasoningDifficulty: Medium

PT13 S4 Q4 Explanation

Kim: Some people claim that

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

TopicsNecessary Assumption

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Stimulus

Kim: Some people claim that the battery‐powered electric car represents a potential solution to the problem of air pollution. But they forget that it takes electricity to recharge batteries and that most of our electricity is generated by burning polluting fossil fuels. Increasing the number of electric cars on the road would it would at best be an exchange of one source of fossil‐fuel pollution for another.

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
4.

Which one of the following is an assumption on which Kim’s

Answer choices

  1. Trap4% picked this

    Replacing gasoline-powered cars with battery- powered electric cars will not lead to a net increase in the total number

  2. Trap1% picked this

    Gasoline-powered cars are currently not the most significant source of

  3. Trap10% picked this

    Replacing gasoline-powered cars with battery- powered electric cars is justified only if electric cars produce

  4. Trap1% picked this

    While it is being operated, a battery-powered electric car does not cause any

  5. Correct83% picked this

    At least some of the generating facilities built to meet the demand for electricity for battery- powered electric cars would be of

    Why this is right

    Answer E is correct.

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

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