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 pin that causes minimum stress in dentin is \nSelect and explain. \nA. Threaded pin, B. Cemented pin, C. Amalga pin, D. Friction lock pin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]