This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: International health agencies, Subject name: Social & Preventive Medicine
World health day is celebrated every year on:- 
Select and explain. 
A. 31st march, B. 7th april, C. 31st may, D. 1st December
B: 7th april
Answer: B: 7th april 
Explanation: 7th April World health day Days of public health impoance Day Public health impoance 30th January Anti-leprosy day 2nd Wednesday of March No smoking day 24th March Anti-TB day 7th April World health day 31st May No tobacoo day 5th June World environment day 1st July Doctors day 8th September World literacy day 10th November Universal immunization day 1st December World Aids day