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: Social & Preventive Medicine
Sputum can be sterilized by all of the following, EXCEPT: 
Select and explain. 
A. Chlorhexidine, B. Cresol, C. Boiling, D. Autoclaving
A: Chlorhexidine
Answer: A: Chlorhexidine 
Explanation: Sputum can be disinfected using: 5% cresol Burning Boiling Autoclaving Ref: Park 21st edition, page 119.