Concept:Identify the organs that belong specifically to the human respiratory system.Explanation:• The trachea (windpipe) carries air to the lungs.• The alveoli are tiny air sacs in the lungs where gas exchange occurs.• Fallopian tube, esophagus, and duodenum belong to other body systems, not the respiratory system.• Therefore, the pair that are both parts of the respiratory system is trachea and alveoli.Answer:C. Trachea and alveoli