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': 'Developmental depressions on both mesial and distal sides of roots are seen in: \nSelect and explain. \nA. Mandibular central incisor, B. Maxillary canines, C. Mesial root of mandibular 1st molar, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Deep concavities on distal surface are present in – Maxillary 1st premolar\nDeep concavities on distal surface are present in – Maxillary 1st molar\nDevelopmental depressions on both mesial and distal sides of roots are seen in – Mandibular central incisors, upper canines, mesial root of mandibular 1st molar.', 'role': 'assistant'}]