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': 'Which of the following factors are important when space maintenance is considered after the untimely loss of primary teeth? \nSelect and explain. \nA. Chronologic age of patient, B. Skeletal age of patient, C. Dental age of patient, D. Biologic age of patient', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]