Question

what gets trapped by cilia and mucus in the respiratory tract?
oxygen and carbon dioxide
liquids that you drink
large airborne particles

Explanation:

The cilia and mucus in the respiratory tract act as a filtering system for inhaled air. Oxygen and carbon dioxide are gases that are exchanged in the lungs, not trapped by this mucus-cilia system. Ingested liquids pass through the digestive tract, not the respiratory tract's mucus-cilia barrier. Large airborne particles like dust, pollen, or bacteria are caught by mucus and moved out by cilia to prevent them from entering the lungs.

Answer:

large airborne particles