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': 'The following statements are true regarding botulism except - \nSelect and explain. \nA. Infant botulism is caused by ingestion of preformed toxin, B. Clostridium botulinum A, B, C and F cause human disease, C. The gene for botulinum toxin is encoded by a bacteriophage, D. Clostridium baratti may cause botulism', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. is \'a\' i.e., Infant botulism is caused by ingestion of preformed toxin . Infant botulism is caused by ingestion of spores. Spores are ingested in food, get established in the gut and there produce the toxin. "Seven main types of C. botulinum, designated A - G, produce antigenically distinct toxins with pharmacologically identical action. All types can cause human disease, but type A, B and E are most common". (In Harrison & Ananthanarayan, eight types of C. botulinum A, B, CI, C2, D, E, F, G have been mentioned). . Toxin production in clostridium botulinum appears to be determined by presence of bacteriophage (at least in type C & D). . "Clostridium butyricum and clostridium baratti have also been found to produce toxin". - Harrison 16th/e 843 - Any strain producing toxin will obviously cause botulism.', 'role': 'assistant'}]