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': 'The pocket epithelium shows a series of histopathological changes. Which of the following is true in this regard? \nSelect and explain. \nA. Necrotic changes, B. Proliferative changes, C. Degenerative changes, D. Proliferative and degenerative changes', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]