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 standard perforated tray for use with alginate impression materials may be brought to more customized contour by: \nSelect and explain. \nA. Utility wax, B. Base plate wax, C. Beading wax, D. Boxing wax', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]