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': 'What is the minimal occlusal thickness that will provide resistance to fracture of amalgam: \nSelect and explain. \nA. 1.0 mm, B. 1.2 mm, C. 1.5 mm, D. 1.8 mm', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]