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
Reason associated with the formation of pulp polyp: 
Select and explain. 
A. Ample vascularity of the young pulp., B. Adequate exposure for drainage., C. Tissue proliferation., D. All of the above.
D: All of the above.
Answer: D: All of the above. 
Explanation: Hyper pulpitis
Hyperplastic pulpitis (pulp polyp) is a form of irreversible pulpitis that originates from overgrowth of a chronically inflamed young pulp onto the occlusal surface. It is usually found in carious of young patients. Ample vascularity of the young pulp, adequate exposure for drainage, and tissue proliferation are associated with the formation of hyperplastic pulpitis