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: Surgery
[{'content': 'Features of mycotic aneurysm are all except \nSelect and explain. \nA. Bacterial endocarditis is common etiology, B. Commonly it is fusiform aneurysm, C. Aorta and visceral vessels affected commonly, D. Multilobed aneurysm with narrow neck', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Mycotic aneursm is commonly saccular.', 'role': 'assistant'}]