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': 'Minimum dose of tetracycline which will show tooth discoloration and enamel hypoplasia: \nSelect and explain. \nA. 5 mg/kg body weight, B. 15 mg/kg body weight, C. 30 mg/kg body weight, D. 50 mg/kg body weight', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]