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: Pathology
An adult old man gets burn injury to his hands. Overfew weeks, the burned skin heals without the need for skin grafting. The most critical factor responsible fohe rapid healing in this case is: 
Select and explain. 
A. Remnant skin appendages, B. Underlying connective tissues, C. Minimal edema and erythema, D. Granulation tissue
A: Remnant skin appendages
Answer: A: Remnant skin appendages 
Explanation: . Remnant skin appendages