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': 'Cavosurface angle for amalgam is: \nSelect and explain. \nA. >90°, B. < 90°, C. 90°, D. 0°', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The design of the cavosurface angle depends on the restorative material being used. Because of the low edge strength of amalgam and glass-ceramic, a 90-degree cavosurface angle produces maximal strength for these materials.\nSturdevants operative dentistry 7th edition page 132.', 'role': 'assistant'}]