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': 'Which premolar would be the most likely to have a single pulp horn? \nSelect and explain. \nA. Maxillary first., B. Mandibular first., C. Mandibular second., D. Maxillary second.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Mandibular first premolar is most likely to have a single pulp horn', 'role': 'assistant'}]