Which epithelium lines the respiratory tract and is associated with mucus movement?

• A. Simple squamous epithelium
• B. Pseudostratified ciliated columnar epithelium with goblet cells
• C. Stratified squamous epithelium
• D. Simple cuboidal epithelium

Answer: (B)

The main idea is the mucociliary clearance in the respiratory tract. The lining is pseudostratified ciliated columnar epithelium with goblet cells, which together enable mucus movement: goblet cells produce mucus to trap dust and pathogens, and the cilia beat in a coordinated fashion to sweep that mucus up toward the throat. This ciliated, mucus-secreting epithelium is characteristic of the trachea and main bronchi, supporting ongoing cleaning of the airway. Other options lack this combination—simple squamous is too thin for protection and gas exchange surfaces, stratified squamous resists abrasion in areas like the oral cavity, and simple cuboidal lacks both cilia and mucus-producing goblet cells.