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: Medicine
[{'content': "The most common cause of facial palsy is - \nSelect and explain. \nA. Bell's palsy, B. Cuillain-Bare syndrome, C. Parotid tumour, D. Injury to the facial nerve", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]