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
[{'content': 'The most important criterion of success in a pulpotomy in a young permanent central incisor would be whether. \nSelect and explain. \nA. The uncompleted root end would complete its development, B. The root end remained open if not fully developed when treatment was started, C. A bridge of secondary dentin, became radiographically demonstrable, D. Pulp stones were in evidence several months after treatment', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]