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
Post-treatment apical periodontitis in an endodontically treated tooth is called as: 
Select and explain. 
A. Recurrent apical periodontitis., B. Persistent apical periodontitis., C. Phoenix abscess., D. Chronic periapical abscess.
B: Persistent apical periodontitis.
Answer: B: Persistent apical periodontitis. 
Explanation: Persistent Apical Periodontitis
Persistent apical periodontitis is a post-treatment apical periodontitis in an endodontically treated tooth