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
Irradiation can be used to sterilize all except 
Select and explain. 
A. Bone graft, B. Suture, C. Artificial tissue graft, D. Bronchoscope
D: Bronchoscope
Answer: D: Bronchoscope 
Explanation: None