Passage Summary: Brian quit his daily fast-food habit for a healthy diet and feels better, so he's convinced that the specific combination of bread and meat was the culprit all along.

Conclusion: Combining bread and meat in a single meal is inherently unhealthy.

Reasoning: Brian stopped eating fast-food cheeseburgers and started a diet of lean meats, fruits, and vegetables, which resulted in improved health markers like lower blood pressure and cholesterol.

Analysis: Brian is a victim of his own enthusiasm, failing to realize that he changed far too many variables at once to pin his success on the 'bread plus meat' rule. This is a classic correlation-versus-causation flaw; he ignores the fact that cutting out greasy fast food and adding vegetables would improve anyone's health, regardless of whether they ate a sandwich. Look for an answer that points out his failure to consider these other obvious factors. It's the logical equivalent of someone quitting smoking and starting marathons, then attributing their health to a new pair of socks.