This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neuroradiology, Subject name: Radiology
[{'content': 'Swirl sign is associated with \nSelect and explain. \nA. Subdural hematoma, B. Epidural hematoma, C. Subarachnoid hematoma, D. Acute bleed', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Swirl sign is a hypodense area noted within a hyperdense Epidural hematoma suggestive of active bleeding, a hyperacute unclotted blood.', 'role': 'assistant'}]