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
Apexification is the treatment of choice for a permanent
tooth with wide open apex when 
Select and explain. 
A. The pulp is necrotic, B. The pulp is vital, C. The pulp and root canals are calcified, D. There is a traumatic pulp exposure during cavity preparation
A: The pulp is necrotic
Answer: A: The pulp is necrotic 
Explanation: None