The separates the upper and lower respiratory tract.
bronchi
larynx
epiglottis
palatine tonsil

Option C, epiglottis

Explanation:

Epiglottis is a flap structure located at the larynx opening which is a separator between the upper and lower respiratory tract.

The upper part of the respiratory tract consists of Nostrils, Nasal Cavities, Pharynx, Epiglottis, and the Larynx.

After the Larynx, the upper respiratory tracts connects the trachea from where the lower respiratory tract starts. The lower respiratory tract consists of Trachea, Bronchi, Bronchioles, and the Lungs.

Hence, option C is the correct.

children tend to take more after their grandparents more than their parents. it’s the dna you received that was passed down to you somewhere in your family. maybe one of your grandparents had/has straight hair and you might have gotten it from them.