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
The age changes in the pulp include 
Select and explain. 
A. Decreased cellularity, B. Increase in fibers with bundle formation, C. Degeneration of nerves and calcifications, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None