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
WHO formation day is – 
Select and explain. 
A. 5th may, B. 7th April, C. 10th june, D. 10th july
B: 7th April
Answer: B: 7th April 
Explanation: The constitution came into force on 7th April 1948, which is celebrated every year as world health day.