Passage Summary: Even though most types of mammals in North America aren't rodents, the actual number of individual rodents is so high that they make up the majority of the mammal population.

Reasoning: N/A

Analysis: Since this is a 'Most Strongly Supported' question, we must treat the premises as absolute facts and look for a logical inference. We have a contrast between species diversity and individual population: rodents have low species diversity (relative to all mammals) but extremely high individual counts. This implies that the average rodent species has a much larger population than the average non-rodent species. Look for an answer that synthesizes these two numerical facts into a single statement about population density or species distribution.