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
Regeneration of lost periodontium involves 
Select and explain. 
A. Healing by new attachment formation, B. Healing by long junctional epithelium formation, C. Healing by re-attachment, D. Healing by scar formation
A: Healing by new attachment formation
Answer: A: Healing by new attachment formation 
Explanation: None