Passage Summary: A bird's spleen size tells you if it's healthy. Scientists noticed that birds caught by predators usually have smaller spleens than birds that died in accidents.

Reasoning: Spleen size is a reliable metric for avian health, and birds killed by predators were found to have smaller spleens than those killed by accidents.

Analysis: Since the stimulus establishes that small spleens are a sign of poor health, we can infer a connection between the two groups of birds mentioned. If the predator-killed birds had smaller spleens, they were likely less healthy than the birds that died in accidents. Look for an answer that suggests predators are more likely to catch the sickly members of a bird population. This is a classic 'Most Strongly Supported' scenario where you combine two premises to reach a logical deduction.