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
Phentom tooth pain is persistent pain after RCT, more than 
Select and explain. 
A. 2 months, B. 3 months, C. 5 months, D. 6 months
D: 6 months
Answer: D: 6 months 
Explanation: None