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: Surgery
[{'content': 'During extractions of maxillary second molar a 0.5mm perforation is created in maxillary sinus. The appropriate treatment would be to: \nSelect and explain. \nA. Perform cald well-Luc procedure, B. Smoothen the bone and place suture across socket, C. Pack the opening with iodoform gauge and allow to heal by secondary intention, D. No treatment necessary', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]