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': 'In acute sinusitis,the sinus more involved in children is: \nSelect and explain. \nA. maxillary, B. Sphenoid, C. Ethmoid, D. Frontal', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Most common sinus effected in children-ethmoid most common sinus effected in adult-Maxillary Ref.Dhingra 6/e,p 193', 'role': 'assistant'}]