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: Radiology
[{'content': 'Extra axial enhancing lesion on MRI. The most likely diagnosis is: \nSelect and explain. \nA. Meningioma, B. Ependymoma, C. Arachnoid cyst, D. Lipoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: After glioblastomas, meningiomas are the second most common brain tumor, and the most common extra axial tumor. Ref: Essentials of Clinical MR edited by Val Runge, John Morelli, 2010, Chapter 4', 'role': 'assistant'}]