This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Paranasal Sinuses, Subject name: ENT
[{'content': 'First sinus to develop - \nSelect and explain. \nA. Ethmoid, B. Maxillary, C. Sphenoid, D. Frontal', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. is \'b\' i.e., Maxillary "Development of the maxillary sinus begins by the 65th day of gestation, making it the first sinus to develop in utero _________Essential otolaryngologyo Most common sinus affected by sinusitis overall- Maxillaryo Most common sinus affected in adult- Maxillaryo Most common sinus affected in children- Ethmoido Least common sinus affected- Sphenoido Sinuses involved in order of frequency- Maxillary > Frontal > Ethmoid > Sphenoid', 'role': 'assistant'}]