Answer
c.
Work Step by Step
Option a. is incorrect. The trachea is the windpipe that leads air from the larynx into the bronchi.
Option b. is incorrect. The epiglottis is a piece of tissue that covers up the entrance into the trachea when we're eating to ensure that food does not enter the lungs.
Option d. is incorrect. The larynx, or the voice box, connects the pharynx and the trachea.
Option c. is correct. The diaphragm is a large, flattened muscle that contracts or relaxes to change the volume of the chest cavity and the lungs during breathing.
