Which tissue type forms a protective surface and may be keratinized on the skin?

• A. Epithelium
• B. Stratified squamous
• C. Simple columnar
• D. Pseudostratified epithelium

Answer: (B)

Protection against abrasion is provided by a tissue that has multiple cell layers, with the outermost layer capable of becoming keratinized to form a tough, waterproof surface. Stratified squamous epithelium fits this role perfectly: it has several layers of cells, and in the skin the surface layer keratinizes, producing a durable, protective coat. This contrasts with simple columnar epithelium, which is a single cell layer specialized for secretion and absorption; pseudostratified epithelium may look layered but is still a single layer and typically lines passages like the respiratory tract rather than forming a durable skin surface. Epithelium is a broad term and doesn’t specify the layered, protective, keratinizing arrangement seen in the epidermis.