This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharynx, Subject name: ENT
[{'content': 'Passavant ridge is formed by \nSelect and explain. \nA. Superior constrictor and palatopharyngeus, B. Inferior constrictor and palatopharyngeus, C. Superior constrictor and palatoglossus, D. Inferior constrictor and palatoglossus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Passavant ridge Near the superior margin of the pharynx, a few fibers of superior constrictor blend with a band of muscle fibers belonging to the palatopharyngeus muscle These fused fibers form a band or ring around the posterior wall and sidewalls of the nasopharyngeal isthmus When the soft palate is elevated this muscle band appears as a ridge is known as passavant ridge. Ref: PL Dhingra, Diseases of Ear, Nose & Throat, 7th edition, pg no. 271', 'role': 'assistant'}]