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': 'What is the working time of amalgam? \nSelect and explain. \nA. One to two minutes, B. Three to four minutes, C. Five to six minutes, D. Seven to eight minutes', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]