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
Periodontal infection is characterized by increased sulcular levels of: 
Select and explain. 
A. Interleukin, B. TNF β, C. IL - 2, D. None of above
A: Interleukin
Answer: A: Interleukin 
Explanation: None