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: Forensic Medicine
[{'content': 'Primary impact injury to brain: DNB 10 \nSelect and explain. \nA. Concussion, B. Cerebral edema, C. Hypoxic injury, D. Intracerebral hematoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Concussion', 'role': 'assistant'}]