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What is True regarding nasopharynx -a) Passavant's muscle is formed by stylopharyngeusb) Fossa of rosenmuller corresponds to the ICAc) Lower border of the nasopharynx corresponds to the upper faucial pillar.d) Lower border lies at the level of soft palate and explain in detail?
Nasopharyns is the upper part of pharynx situated behind nose and above the lower border of soft palate. Inferiorly it communicates with oropharynx at nasopharyngeal isthmus, and opening which is bounded by lower border of soft palate and posterior wall of nasopharynx (Passavant's ridge). Passavant's ridge is formed by upper fibers of palato phalyngeus muscles.
A narrow vertical slit behind the tubal elevation in lateral wall of nasopharynx leads into a flat pocket of mucous membrane known as pharyngeal or lateral recess or fossa of rosenuller. It corresponds to ICA (internal carotid artery).