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': 'Characteristic of subdural hematoma is – \nSelect and explain. \nA. Convex hyperdensity, B. Concavo convex hyperdense, C. Biconvex hyperdense, D. Concavo convex hypodense', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]