This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and PNS, Subject name: ENT
[{'content': 'Orbital cellulitis most commonly occurs after which sinus infection? \nSelect and explain. \nA. Maxillary, B. Frontal, C. Ethmoidal, D. Sphenoidal', 'role': 'user'}, {'content': 'Answer: C \nExplanation: ANSWER: (C) EthmoidalREF: Dhingra 4th ed p, 182,190However orbital cellulitis can be a complication of maxillary, frontal and Ethmoid sinusitis, Orbital cellulitis is an early complication in Ethmoid sinusitis and hence most common.', 'role': 'assistant'}]