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 base constituents of dental waxes come from three main sources except: \nSelect and explain. \nA. Animal, B. Mineral, C. Insect, D. Vegetable', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]