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
The upper line in the road-to-health card corresponds to: 
Select and explain. 
A. 95th percentile, B. 50th percentile, C. 3rd percentile, D. 90th prercentile
B: 50th percentile
Answer: B: 50th percentile 
Explanation: 50th percentile