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': 'Linear coefficient of thermal expansion of composites is \nSelect and explain. \nA. 1 ppm/ oC, B. 40 ppm/ oC, C. 260 ppm/ oC, D. 1000 ppm/ oC', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Linear coefficient of thermal expansion:\n\nTOOTH :\xa09-11 PPM/ oC\xa0\nAMALGAM :\xa025\xa0\nGOLD :\xa015\xa0\xa0\nCOMPOSITES :\xa040\xa0\nGIC :\xa025\xa0\nDENTAL WAXES :\xa0HIGHEST 260-600 PPM/ oC\xa0\n\nReference- Sturdevant 6th ed P:237', 'role': 'assistant'}]