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': 'Second step of respective osseous surgery: \nSelect and explain. \nA. Vertical grooving, B. Radicular blending, C. Gradualizing bone margins, D. Flattening of 1/P bone', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Steps for Resective Osseous Surgery\n\nVertical grooving\nRadicular blending\nInterproximal bone flattening\nGradualization of marginal bone', 'role': 'assistant'}]