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 elastomer having the longest curing time is \nSelect and explain. \nA. Polysulfide, B. Poly ether, C. Addition silicone, D. Condensation silicone', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]