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
Among the toxin produced by botulinum, the nonneurotoxic one is: 
Select and explain. 
A. A, B. D, C. Cl, D. C2
B: D
Answer: B: D 
Explanation: Ans. is. 'd' i. e. D