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 one of the following is not a normal anatomical feature of mandibular incisors? \nSelect and explain. \nA. Bifurcated roots., B. Inconspicuous cingula., C. Four developmental lobes., D. Incisal edges placed slightly lingually.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Bifurcated roots are not a normal feature of mandibular incisors.', 'role': 'assistant'}]