Scientist: Laboratory animals have access

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

TopicsNecessary Assumption

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Stimulus

Scientist: Laboratory animals have access to ample food, and they get relatively little exercise. These factors can skew the results of research using animals, since such studies often rely on the assumption that the animal subjects are healthy. For instance, animal studies that purport to show that granted that their subjects were not overfed to begin with.

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

The scientist's argument requires assuming which one of

Answer choices

Illegal Negation8% picked this
Laboratory animals are healthy if they are fed a carefully restricted diet and get
Illegal Negation
8%
Correct83% picked this
Laboratory conditions that provide animals with ample food but relatively little exercise can be unhealthy
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.
83%
Trap6% picked this
It is not unusual for animals outside of laboratory settings to have access to ample food and
Out of Scope: outside of lab settings
6%
Trap2% picked this
Some animal studies take into consideration the differences between the living conditions of laboratory animals and
Out of Scope: outside of lab settings Opposite (if anything): taking into consideration
2%
Out of Scope: unlimited food1% picked this
When provided with unlimited food over a long period of time, animals show little day-to-day variation
Out of Scope: unlimited food
1%

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