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: Pathology
[{'content': 'Ascending aoa involvement is the commonest site of which aneurysm: \nSelect and explain. \nA. Syphilitic, B. Atherosclerotic, C. Mycotic, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Mycotic', 'role': 'assistant'}]