This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'Catalase negative member of the family Enterobacteriaceae is (NOT RELATED) \nSelect and explain. \nA. Salmonella typhi, B. Proteus vulgaris, C. Shigella dysenteriae serotype 1, D. Escherichia coli', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The general finding that members of the family enterobacteriaceae produce catalase has impoant exceptions in Shigella dysenteriae serotype 1 and a few strains of Shigella flexneri (mostly in serotype 4a) which are catalase negative.', 'role': 'assistant'}]