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': 'The predominant organism found in smears of ANUG is \nSelect and explain. \nA. Vibro, B. Fusobacterium, C. Spirochetes, D. Streptococci', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]