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 reason for sealing caries during cavity preparation is: \nSelect and explain. \nA. To eliminate the need for eventual direct pulp capping, B. Produce an aseptic field when pulp exposure is inevitable, C. To allow the formation of secondary dentin before excavation, D. To produce a hard surface as a foundation for subsequent restoration', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]