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': 'Eruption of the permanent maxillary second molar prior to the maxillary second premolar is: \nSelect and explain. \nA. Normal and desirable, B. Abnormal and undesirable, C. Abnormal and desirable, D. Normal and undesirable', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]