This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Salivary Gland), Subject name: Surgery
[{'content': 'Most common cause of acute parotitis - \nSelect and explain. \nA. S. Aureus, B. S. Pneumonia, C. Klebsiella, D. S.Viridans', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Staph Aureus o MC organism is staph aureus >> str. viridans >> pneumococcus.", 'role': 'assistant'}]