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
Which of the following organisms is NOT implicated in  the etiology of Periodontal disease 
Select and explain. 
A. Bacteroides, B. Wolinella, C. Neisseria, D. Eikenella
C: Neisseria
Answer: C: Neisseria 
Explanation: None