What is the smallest part of the adult airway?

The glottic opening is considered the smallest part of the adult airway because it specifically refers to the space between the vocal cords located within the larynx. This anatomical structure plays a critical role in both breathing and phonation. It acts as the transition point from the upper airway to the lower airway, controlling airflow into the trachea and helping to protect the airway during swallowing by closing off to prevent aspiration.

The other structures mentioned, such as the pharynx, larynx, and trachea, are larger in comparison. The pharynx encompasses a larger area that includes passageways for both the respiratory and digestive systems. The larynx, while it houses the glottic opening, is also wider and includes additional structures such as the epiglottis and the vocal folds. The trachea is the main airway leading to the lungs and is significantly more extensive than the glottic opening. Hence, the glottic opening is specifically identified as the narrowest part, which emphasizes its importance in airway management and resuscitation scenarios.