This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
Prevalence of tuberculosis infection is determined by - 
Select and explain. 
A. Sputum examination, B. Mantoux, C. Clinical examination, D. MMR
B: Mantoux
Answer: B: Mantoux 
Explanation: The tuberculin (Mantoux) test is the only means of estimating the prevalence of infection in a population . Ref:PARK&;S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE 23rd edition , Page 185