Logical ReasoningDifficulty: Medium

PT11 S2 Q13 Explanation

Emissions from automobiles that burn gasoline

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

TopicsNecessary Assumption

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Stimulus

Emissions from automobiles that burn gasoline and automobiles that burn diesel fuel are threatening the quality of life on our planet, contaminating both urban air and global atmosphere. Therefore, the only effective way to reduce such emissions is to replace the conventional diesel fuels, such as methanol, that create fewer emissions.

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
13.

Which one of the following is an assumption on which the

Answer choices

  1. Correct73% picked this

    Reducing the use of automobiles would not be a more effective means to reduce automobile emissions 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.

  2. Trap15% picked this

    There is no fuel other than methanol that is cleaner-burning than both diesel

  3. Trap4% picked this

    If given a choice of automobile fuels, automobile owners would not select

  4. Trap5% picked this

    Automobile emissions constitute the most serious threat to the

  5. Trap2% picked this

    At any given time there is a direct correlation between the level of urban air pollution and the level of contamination

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