Which of the following are considered the main parts of the respiratory system?

The primary components of the respiratory system are essential for the process of breathing and gas exchange. The correct option includes the nose, pharynx, larynx, and trachea.

The nose serves as the entry point for air, filtering, warming, and humidifying it. The pharynx acts as a passageway for both air and food, positioning it at the junction of the respiratory and digestive pathways. The larynx, often referred to as the voice box, plays a crucial role in protecting the airway during swallowing and in producing vocal sounds. Finally, the trachea is the windpipe that conducts air from the larynx into the bronchi and subsequently into the lungs, where gas exchange occurs.

The other options include components that do not fully represent the main parts of the respiratory system or mix gastrointestinal elements (like the esophagus and stomach) that are not involved in respiration. For instance, the esophagus is part of the digestive system, while the cardiac term refers to the heart, which is part of the circulatory system rather than the respiratory anatomy. Thus, the option including the nose, pharynx, larynx, and trachea is most accurate in defining the key structures of the