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
The predominant organism found in smears of ANUG is 
Select and explain. 
A. Vibro, B. Fusobacterium, C. Spirochetes, D. Streptococci
C: Spirochetes
Answer: C: Spirochetes 
Explanation: None