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': 'ANUG is caused by \nSelect and explain. \nA. Borrelia vincenti and fusobacterium, B. Actinomycetam comitans, C. Actinomyces nausetadii, D. Streptococcus mutans', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]