What is the function of the cilia on the cells that line the bronchial tree? A. They help mix the inhaled fresh air with the residual air contained in the bronchial tree. B. They slow the movement of air to allow for effi cient exchange of gases. C. They move the mucus on the cell surface up out of the bronchial tree. D. They fi lter particles from inhaled air.
Option C. Function of cilia:- They move the mucus on the cell surface up out of the bronchial tree.
