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
Delayed tuberculin test response is due to: September 2004 
Select and explain. 
A. B lymphocytes, B. T lymphocytes, C. Monocytes, D. Histiocytes
B: T lymphocytes
Answer: B: T lymphocytes 
Explanation: Ans. B i.e. T lymphocytes