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': 'Function of the maxillary sinus is: \nSelect and explain. \nA. Protects the skull against mechanical shock., B. Defence against bacterial infection., C. It warms and moistens the inspired air., D. All of the Above.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Functional Importance and Clinical Considerations\nMany functions are attributed to maxillary sinus. Being an air\xa0space it lessens the weight of skull, gives resonance to the\xa0voice and protects the skull against mechanical shock. It\xa0warms and moistens the inspired air. The lysozyme it produces is bactericidal and thus contributes to the defense\xa0against bacterial infections.', 'role': 'assistant'}]