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': 'Sequential steps for resective osseous surgery are \nSelect and explain. \nA. radicular blending, vertical grooving, flattening interproximat bone, gradualizing marginal bone, B. vertical grooving, flattening interproximal bone, gradualizing marginal bone, radicular blending, C. vertical grooving, radicular blending, flattening interproximal bone, gradualizing marginal bone, D. vertical grooving, radicular blending, gradualizing marginal bone, flattening interproximal bone', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]