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': 'Material of choice for incremental border moulding is: \nSelect and explain. \nA. Polyether, B. Greenstick compound., C. Polysulphide, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Incremental or sectional border moulding: It is a procedure, in which portions of the periphery of the tray are refined individually. The material of choice for this procedure is green stick compound', 'role': 'assistant'}]