Cilia Lining the Respiratory Tubes Beat Mucus Upward in Order

Cilia lining the respiratory tubes beat mucus upward in order to:

A) moisten the bronchioles.
B) conduct the mucus that contains particles to the pharynx and away from the lungs.
C) provide mucus to the lungs to prevent them from dehydrating.
D) lubricate the throat for easier swallowing.
E) promote gas exchange by providing mucus for the respiratory surfaces.