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
Sputum examination for AFB is a type of- 
Select and explain. 
A. Primary prevention, B. Secondary prevention, C. Teiary prevention, D. Primordial prevention
B: Secondary prevention
Answer: B: Secondary prevention 
Explanation: Ans. is 'b' i.e., Secondary prevention Sputum for AFB is used for diagnosis of TB, so that treatment can be staed