Stimulus
The size of the spleen is a good indicator of how healthy a bird is: sickly birds generally have significantly smaller spleens than healthy birds. Researchers found that, in general, birds that had smaller spleens than birds killed accidentally.
What this question is testing
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.
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