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
In AIDS patients, occurrence of severe and acute periodontal disease are due to 
Select and explain. 
A. Reduced number of T -cells, B. Release of lymphokines, C. Cytotoxic reaction, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None