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
Vital bleaching causes 
Select and explain. 
A. Internal resorption, B. Cervical resorption, C. External resorption, D. Periapical periodontitis
D: Periapical periodontitis
Answer: D: Periapical periodontitis 
Explanation: None