Common Tissues in Trachea and Bronchus Walls

Steps:

• Trachea wall contains ciliated pseudostratified columnar epithelium, smooth muscle, and cartilage rings; lacks squamous epithelium.
• Bronchus wall contains ciliated pseudostratified columnar epithelium, smooth muscle, and cartilage plates; lacks squamous epithelium.
• Common tissues are ciliated epithelium (present in both) and smooth muscle (present in both), with squamous epithelium absent.
• Option C matches: ciliated ✓, squamous X, smooth muscle ✓.

Why C is correct:

• Respiratory epithelium in trachea and bronchi is ciliated pseudostratified columnar for mucociliary clearance, with smooth muscle for constriction; squamous epithelium lines alveoli, not these airways.

Why the others are wrong:

• A: Includes squamous epithelium, absent in both trachea and bronchus walls.
• B: Excludes ciliated epithelium, essential in both for trapping particles.
• D: Includes squamous epithelium and excludes ciliated epithelium, reversing the actual presence.

Final answer: C