This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Social & Preventive Medicine
[{'content': "In WHO growth chart 'Lower reference curve' represents \nSelect and explain. \nA. 3rd percentile, B. 50th percentile, C. 80th percentile, D. 95th percentile", 'role': 'user'}, {'content': 'Answer: A \nExplanation: (A) 3rd percentile > WHO reference curves are based on extensive cross-sectional data of well-nourished healthy children, assembled by the United States National Centre for Health Statistics (NCHS), which are considered the best available for international use.# WHO growth chart> The upper reference curve represents the median (50th percentile) for boys (slightly higher than that for girls), and the lower reference curve the 3rd percentile for girls (slightly lower than that for boys).> Thus the chart can be used for both sexes.', 'role': 'assistant'}]