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: Microbiology
Positive tuberculin test means? 
Select and explain. 
A. Resistance to TB, B. Susceptibility to TB, C. Hypersensitivity, D. None of the above
C: Hypersensitivity
Answer: C: Hypersensitivity 
Explanation: Ans. is 'c' i.e., Hypersensitivity A positive tuberculin test indicates hypersensitivity to tuberculoprotein, it may be due to : Active infection Subclinical infection Past infection BCG vaccination In overwhelming tuberculosis (fulminant cases) due to depressed cellular immunity montoux test may be false negative.