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
Gingivitis 
Select and explain. 
A. Inevitably progresses to periodontitis, B. Affects approximately 40% of adolescents, C. Is characterized by true pocketing, D. Is a reversible lesion
D: Is a reversible lesion
Answer: D: Is a reversible lesion 
Explanation: None