Consists of a single layer of cells attached to a basement membrane. There are four types squamous or pavement, cuboidal, columnar and ciliated.

• A. Simple epithelium
• B. Stratified epithelium
• C. Endothelium
• D. Connective tissue

Answer: (A)

A single layer of cells attached to a basement membrane is the defining feature of simple epithelium. The four forms—squamous (flat), cuboidal (cube-shaped), columnar (tall), and ciliated—are the common shapes you see within this one-layer category. That’s why this option fits best: it matches the organization (one cell layer) and the four shapes listed are the typical types of simple epithelium.

Stratified epithelium wouldn’t fit because it has multiple layers. Endothelium is a specific type of simple epithelium that lines blood vessels, so it’s still part of the simple epithelium family rather than a separate category. Connective tissue is a different tissue type altogether and doesn’t form a single-layer epithelium on a basement membrane.