Kupffer cells are similar in function to

The sound-producing organ in the human respiratory system is . . . . . . .

The narrowest and most numerous tubes of the lungs are termed as:

During swallowing, the glottis can be covered by a thin elastic cartilaginous flap called $A$ to prevent the entry of food into the larynx. The trachea is a straight tube extending up to the $B$ cavity, which divides at the level of the $5^{th}$ thoracic vertebra into right and left primary $C$. Choose the correct option for $A, B$, and $C$ from the given four options to complete the above statement with reference to the $NCERT$ textbook.

The trachea and bronchi are provided with $C$-shaped cartilaginous rings which:

The outer pleural membrane is in close contact with the .....