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: Pathology
[{'content': 'A developmental abnormality characterized by the presence of fewer than the usual number of teeth is \nSelect and explain. \nA. Anodontia, B. Oligodontia, C. Microdontia, D. Dens in dente', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]