Which section of the pharynx is associated with the nasal cavity?

The nasopharynx is the section of the pharynx that connects to the nasal cavity. It is located above the soft palate and serves as a passageway for air during breathing. The nasopharynx plays a critical role in the respiratory system by allowing air from the nasal cavity to enter the pharynx and subsequently the larynx and trachea. It is also important in equalizing pressure within the ears via the Eustachian tubes, which open into this area.

Regarding the other sections, the oropharynx is located behind the oral cavity and is involved in both respiratory and digestive functions, but it does not directly connect to the nasal cavity. The laryngopharynx is found below the oropharynx and leads into both the larynx (for air) and esophagus (for food), but it does not connect to the nasal cavity either. The esophagus is a tube that connects the throat to the stomach and is not part of the pharyngeal structure relevant to the nasal cavity. Thus, the relationship of the nasopharynx with the nasal cavity is what makes it the correct choice.