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 aoic aneurysm is: \nSelect and explain. \nA. Syphilis, B. Marfan's syndrome, C. Atherosclerosis, D. Congenital", 'role': 'user'}, {'content': "Answer: C \nExplanation: Answer is C (Atherosclerosis) 'The most common pathologic condition associated with aoic aneurysm is Atherosclerosis':", 'role': 'assistant'}]