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': 'Dentin formation begins in \nSelect and explain. \nA. Morphogenic stage, B. Organizing stage, C. Terminal phase of organizing stage, D. Terminal phase of formative stage', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]