This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and paranasal sinuses, Subject name: ENT
[{'content': 'Most common complication of Sinusitis is \nSelect and explain. \nA. Orbital cellulitis, B. Meningitis, C. Brain abscess, D. Septicemia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Orbital cellulitis is an infection of the soft tissues of the orbit posterior to the orbital septum. Orbital cellulitis is caused most commonly in all age groups by ethmoid sinusitis. The organisms gain access to the orbit through thin bones of the orbital walls, venous channels, foramina, and dehiscence. Orbital cellulitis resulting from infection of the maxillary sinus secondary to dental infections can be caused by microorganisms indigenous to the mouth.', 'role': 'assistant'}]