Passage Summary: Researchers released some hand-raised opossums into the wild and most were eaten by foxes. This led them to believe that predators, not a lack of food, are the real reason these animals are in trouble.

Conclusion: The primary threat to the ringtail opossum is non-native predators rather than a lack of food.

Reasoning: A high percentage of captive-raised opossums were killed by non-native foxes after being released into the wild.

Analysis: The argument makes a significant leap by assuming that what happens to captive-raised, orphaned opossums is representative of what happens to the wild population. To strengthen this, we need to bridge the gap between these two groups or rule out other variables. Look for an answer that suggests food was actually plentiful in the area or that wild-born opossums are just as vulnerable to foxes as the captive-raised ones. We want to ensure the fox-related deaths weren't just a result of the orphans being 'soft' or unskilled at survival.