Bronchial tissue components

Steps:

• Recall bronchial histology: lined by pseudostratified ciliated columnar epithelium containing epithelial cells for protection and mucociliary clearance.
• Note structural layers: bronchi contain smooth muscle in walls to control airway diameter and prevent collapse.
• Evaluate goblet cells: absent in bronchi, as mucus production occurs via submucosal glands, unlike in trachea where goblet cells predominate.
• Determine correct statements: only 2 and 3 align with bronchial anatomy.

Why D is correct:

• Bronchi feature epithelial cells for lining and muscle tissue for constriction, per standard respiratory system structure.

Why the others are wrong:

• A includes 1, but goblet cells are not present in bronchi.
• B includes 1 but excludes 3, yet muscle tissue is essential.
• C includes 1 but excludes 2, yet epithelial cells form the inner layer.

Final answer: D