This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Miriam, a college student with acute rhinitis sees the campus nurse because of excessive nasal drainage. The nurse asks the patient about the color of the drainage. In acute rhinitis, nasal drainage normally is: \nSelect and explain. \nA. Yellow, B. Green, C. Clear, D. Gray', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Normally, nasal drainage in acute\xa0rhinitis\xa0is clear. Yellow or green drainage indicates spread of the infection to the\xa0sinuses. Gray drainage may indicate a secondary infection.', 'role': 'assistant'}]