This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Most common viral disease affecting parotid glands \nSelect and explain. \nA. Mumps, B. Measles, C. Rubella, D. varicella', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Mumps is characterised by non suppurative enlargement and tenderness of one or both the parotid glands Reference: Park&;s Textbook of Preventive and Social medicine; 24th edition; Page no.162', 'role': 'assistant'}]