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
HEPA filter is used to disinfect ? 
Select and explain. 
A. Water, B. Air, C. Culture, D. Blood
B: Air
Answer: B: Air 
Explanation: Ans. is 'b' i.e., Air HEPA (High-efficiency paiculate air) filter is used to remove microorganisms from air. HEPA filter traps airborne paicles and microbes. It can remove > 95% of all paicles including microorganisms with a diameter > 0.3 p.m.