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 most common sequel of gingivitis: 
Select and explain. 
A. Pericoronitis, B. Periodontitis, C. Periodontosis, D. Periapical pathology
B: Periodontitis
Answer: B: Periodontitis 
Explanation: None