Final answer:
B) Decreased mood and irritability.
Morgan experienced decreased mood and increased irritability due to his 30-day McDonald's-only diet, reflecting the impact of diet on emotional well-being.
Step-by-step explanation:
The student's question asks about the emotional and behavioral changes experienced by Morgan as a result of his 30-day experiment eating nothing but McDonald's, as depicted in the documentary 'Super Size Me'. The correct answer to the question is B) Decreased mood and irritability. Throughout the experiment, Morgan reported experiencing significant changes in his physical and emotional well-being, including mood swings, lethargy, and a decrease in motivation. These negative effects highlighted the impact of a poor diet on overall mental health and can be used to emphasize the importance of nutritional awareness, especially among high school students who are at a critical developmental stage.