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': "According to Bennett's classification, abnormal formation of a part or whole of either arch due to developmental defects of bone is: \nSelect and explain. \nA. Class 1, B. Class 2, C. Class 3, D. Class 4", 'role': 'user'}, {'content': "Answer: B \nExplanation: Bennett's Classification", 'role': 'assistant'}]