Which combining form denotes epithelial tissue; pertaining to or composed of epithelium?

• A. Epitheli/o
• B. Derm/o
• C. Muc/o
• D. Sclero/o

Answer: (A)

Identifying the combining form for epithelium is the main idea. Epithelium is the tissue that lines surfaces and forms glands, so the combining form that denotes this tissue is epitheli/o. When you attach a suffix like -al, you get epithelial, meaning pertaining to or composed of epithelium. The other options point to different tissues—derm/o is skin, muc/o is mucous membranes, sclero/o is hardness—so epitheli/o is the best fit.