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': 'Marginal metal angle for cast inlay is: \nSelect and explain. \nA. 130-140 degree, B. 30-40 degree, C. 90-100 degree, D. Less than 30 degree', 'role': 'user'}, {'content': 'Answer: B \nExplanation: DIFFERENES \xa0BETWEEN INLAY AND AMALGAM RESTORATIONS:', 'role': 'assistant'}]