Logical ReasoningDifficulty: Hard

PT124 S3 Q8 Explanation

Environmentalist: When bacteria degrade

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

TopicsNecessary Assumption

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Stimulus

Environmentalist: When bacteria degrade household cleaning products, vapors that are toxic to humans are produced. Unfortunately, household cleaning products are often found in landfills. Thus, the common practice parks is damaging human health.

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
8.

Which one of the following is an assumption the environmentalist's

Answer choices

  1. Correct72% picked this

    In at least some landfills that have been converted into public parks there are bacteria that

    Why this is right

    This provides the second of the anticipated assumptions in the argument. Unless the bacteria are degrading household cleaning products, the presence of those products do not threaten human health.

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

  2. Reversal5% picked this

    Converting a landfill into a public park will cause no damage to human health unless toxic vapors are produced in that landfill

    This reverses an assumption of DH → TV the argument that toxic vapors damage human health.

  3. Wrong Trigger12% picked this

    If a practice involves the exposure of humans to vapors from household cleaning products, then it causes at least

    The trigger should not be exposure to vapors from household cleaning products, but rather toxic vapors produced when bacteria degrade household cleaning products.

  4. Out of Scope1% picked this

    When landfills are converted to public parks, measures could be taken that would prevent people using the parks from

    Whether the problem could be mitigated is not relevant to whether the problem currently exists.

  5. Too Strong11% picked this

    If vapors toxic to humans are produced by the degradation of household cleaning products by bacteria in any landfill, then the health of

    The trigger has been strengthened to apply to any landfill, while the argument only assumes that human health will be damaged at those landfills converted to public parks.

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