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: Social & Preventive Medicine
[{'content': 'IQ = 51 – \nSelect and explain. \nA. Mild MR, B. Moderate MR, C. Severe MR, D. Profound MR', 'role': 'user'}, {'content': 'Answer: A \nExplanation: IQ between 50-70 is mild mental retardation.', 'role': 'assistant'}]