Logical ReasoningDifficulty: Easy

PT135 S4 Q6 Explanation

The calm, shallow waters of coastal

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

TopicsMust be True

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Stimulus

The calm, shallow waters of coastal estuaries are easily polluted by nutrient-rich sewage. When estuary waters become overnutrified as a result, algae proliferate. The abundant algae, in turn, sometimes provide a rich food source for microorganisms killing most of the fish in the estuary.

What this question is testing

Must be True

Your task

Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.

Common trap

Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.

Winning move

Predict what a right answer must do, then test each choice against the conclusion-evidence gap.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
6.

Which one of the following can be properly inferred from the

Answer choices

  1. Out of Scope2% picked this

    Fish in an estuary that has been polluted by sewage are generally more likely to die from pollution than are fish in an estuary

    The likelihood that fish would die from pollution other than sewage is not discussed in the statements.

  2. Out of Scope4% picked this

    In estuary waters that contain abundant algae, microorganisms that are toxic to fish reproduce more quickly than

    The rate that microorganisms that are not toxic to fish reproduce is not discussed in the statements.

  3. Too Strong3% picked this

    Nutrients and other components of sewage do not harm fish in coastal estuaries in any way other than through the

    The statements do imply that sewage harms fish by way of resulting in a proliferation of toxic microorganisms.

  4. Negation6% picked this

    Algae will not proliferate in coastal estuaries that are not polluted

    That algae will proliferate in estuaries polluted by nutrient-rich sewage, does not imply that they will not proliferate in estuaries that are not polluted.

  5. Correct85% picked this

    Overnutrifying estuary waters by sewage can result in the death of most of the fish

    Why this is right

    This links together S -causes→ FD the causal chain.

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

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