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': 'Which of the following pockets offers best chance for bone regeneration: \nSelect and explain. \nA. Suprabony pocket, B. One - wall infrabony pocket, C. Two - wall infrabony pocket, D. Three - wall infrabony pocket', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]