Logical ReasoningDifficulty: Hard

PT156 S4 Q20 ExplanationAzalea bushes flourish in acidic soil

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

TopicsNecessary Assumption

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Stimulus

Azalea bushes flourish in acidic soil. Clay soil, while rarely acidic, can be mixed with other types of soil to create a soil that is acidic. Hence, to flourish in clay soil.

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
20.

Which one of the following is an assumption on which the

Answer choices, explained

  1. Trap3% picked this

    Mixing an acidic soil with another type of soil always results in

  2. Correct63% picked this

    Clay soil that is mixed with certain other types of soil is

    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. Trap13% picked this

    Whenever clay soil is mixed with other types of soil, an

  4. Trap1% picked this

    Some plants do not flourish in

  5. Trap20% picked this

    Azalea bushes do as well in treated clay soils as in

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