Question

which of the following is not an organ of the respiratory system? a lungs b esophagus c trachea d nasal cavity

Explanation:

The respiratory system is responsible for gas - exchange. Lungs are the main organs for gas - exchange, trachea is the airway, and nasal cavity is the entrance for air. The esophagus is part of the digestive system, which transports food from the mouth to the stomach.

Answer:

B. esophagus