Which description best defines simple epithelium?

• A. A single layer of cells attached to a basement membrane
• B. Multiple layers of cells with different shapes
• C. A dense connective tissue with scattered cells
• D. Muscle tissue with contractile fibers

Answer: (A)

Simple epithelium is defined by a single layer of cells that lines surfaces and sits on a basement membrane. This thin, continuous layer allows efficient exchange, absorption, or secretion at surfaces such as the lining of organs and body cavities. The other descriptions describe different tissues—multiple layers point to stratified epithelium, dense connective tissue is a connective tissue type, and muscle tissue contains contractile fibers—so they don’t fit the definition of simple epithelium.