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': 'What are the requirements of a pontic: \nSelect and explain. \nA. Restore function., B. Permit effective oral hygiene., C. Preserve underlying residual mucosa., D. All of the above.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The requirements of a pontic are:\xa0 \n• Restore function\n• Provide esthetics and comfort\n• Biologically acceptable\n• Permit effective oral hygiene\n• Preserve underlying residual mucosa', 'role': 'assistant'}]