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
Vaccines are sterilised by - 
Select and explain. 
A. Seitz filtration, B. Hot air oven, C. Autoclaving, D. Heat inactivation
D: Heat inactivation
Answer: D: Heat inactivation 
Explanation: Ans. is 'd' i.e., Heat inactivation . Vaccines of nonsporing bacteria are heat inactivated in special vaccine bath at 60degC for one hour.