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': 'According to caries risk assessment which tooth has lowest risk? \nSelect and explain. \nA. Maxillary 1st premolar, B. Maxillary 2nd premolar, C. Mandibular 1st premolar, D. Mandibular 2nd premolar', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Caries risk assessment', 'role': 'assistant'}]