Which statement correctly matches the arterial tunics to their tissue components?

• A. Intima: Endothelium with subendothelial layer; Media: Smooth muscle with elastic fibers; Adventitia: Connective tissue with collagen, nerves, and vasa vasorum.
• B. Intima: Connective tissue with collagen; Media: Endothelium with tight junctions; Adventitia: Elastic fibers.
• C. Intima: Smooth muscle; Media: Endothelium; Adventitia: Adipose tissue and nerves.
• D. Intima: Adventitia; Media: Endothelium; Adventitia: Smooth muscle.

Answer: (A)

Arteries have three tunics organized in a specific way: the innermost tunica intima is lined by endothelial cells with a thin subendothelial layer of connective tissue; the tunica media is a thick middle layer composed mainly of smooth muscle arranged in circular layers and interwoven with elastic fibers to provide strength and the ability to constrict or dilate; the outer tunica adventitia is made of connective tissue rich in collagen and contains nerves and the vasa vasorum that nourish the vessel wall. The statement that correctly matches these components is the one that identifies the intima as endothelium with a subendothelial layer, the media as smooth muscle with elastic fibers, and the adventitia as connective tissue containing collagen, nerves, and vasa vasorum. The other descriptions mix up which tissues belong to which layer (for example, endothelium belongs to the intima, not the media; the adventitia is not simply elastic or adipose tissue).