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': 'Curve of Monson is \nSelect and explain. \nA. An anteroposterior curve, B. Is a lateral molar curve with convexity facing downwards, C. Is a lateral premolar curve with convexity facing upwards, D. A reverse curve', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]