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
[{'content': 'Spores are formed by all except: \nSelect and explain. \nA. E. coli, B. B. anthrex, C. B. cerus, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. a. E. coli', 'role': 'assistant'}]