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: Dental
[{'content': 'All of the following are signs of periodontal trauma except: \nSelect and explain. \nA. Pain, B. Mobility, C. Hypersensitivity, D. Bleeding', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]