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: Dental
[{'content': 'Endemic Disease means that a disease: \nSelect and explain. \nA. Occurs clearly in excess of normal expectancy, B. Is constantly present in a given population group, C. Exhibits seasonal pattern, D. Is prevalent among animals', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]