This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Biomedical Waste Management, Subject name: Social & Preventive Medicine
Quality control agent for Sterilization in Autoclave 
Select and explain. 
A. Bacillus subtilis, B. Bacillus pumilus, C. Bacillus stearothermophilus, D. Bacillus globigi
C: Bacillus stearothermophilus
Answer: C: Bacillus stearothermophilus 
Explanation: Autoclaving Geobacillus stearothermophilus(GBS) Hydroclaving Bacillus subtilis Microwaving Bacillus atrophaeus Dry heat GBS or Bacillus atrophaeus