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': 'Tissue conditioning materials are \nSelect and explain. \nA. Elastomers, B. Elasto polymers, C. Polymers, D. Impression plaster', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]