Structural Components of Trachea and Bronchus Walls

Steps:

• Identify key histological features: hyaline cartilage rings, pseudostratified ciliated columnar epithelium, and submucosal seromucous glands.
• Confirm trachea wall includes all three: incomplete C-shaped cartilage, ciliated epithelium with goblet cells, and glands.
• Confirm primary bronchus wall mirrors trachea: cartilage plates, same epithelium, and glands.
• Match to option A, where all features (✓ ✓ ✓) apply to both structures.

Why A is correct:

• Trachea and primary bronchi share identical wall components per respiratory anatomy, including cartilage for support, cilia for mucociliary clearance, and glands for mucus secretion.

Why the others are wrong:

• B: Falsely indicates bronchus lacks the third feature (e.g., glands present in both).
• C: Incorrectly shows trachea lacks first feature (cartilage essential in trachea).
• D: Denies all features in both, contradicting basic histology.

Final answer: A