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': 'Co-efficient of thermal expansion is highest for: \nSelect and explain. \nA. Amalgam, B. Silicate cement, C. Gold alloy, D. Acrylic resin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]