Which of the following organs is not located in the thoracic cavity?

The figure shows a diagrammatic view of the human respiratory system with labels $A, B, C$,and $D$. Select the option which gives the correct identification and main function and/or characteristic.

Which portion of the human respiratory system is called the sound box?

The total surface area of the human lungs,specifically the respiratory surface area provided by the alveoli,is approximately: (in $; m^{2}$)

Air is breathed through which of the following pathways?

The nasal cavity is divided by a central septum and contains several bony projections called: