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': 'The orifice of the fourth canal in a maxillary molar is usually found: \nSelect and explain. \nA. Under the Distofacial cusp, B. Lingual to the orifice of the Mesiofacial canal, C. On a line running from the distofacial orifice to the Mesiofacial orifice, D. On a Line running from the Lingual orifice to the Distofacial orifice', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]