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': 'True about diphyllobothrium: \nSelect and explain. \nA. Man is single host, B. Iron deficiency anemia is seen, C. Operculated egg is diagnostic, D. Fish is the definitive host', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. c. Operculated egg is diagnostic', 'role': 'assistant'}]