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': 'Most common cause of sudden death is: \nSelect and explain. \nA. Cerebral haemorrhage, B. Arrhythmias, C. Ruptured aortic aneurysm, D. Cancer', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]