Which epithelial membranes protect by forming a lining for all passages that are open to the exterior of the body?

A. Nervous tissue: Nervous tissue is made up of neurons and glial cells, not squamous, cuboidal, or columnar cells.

B. Muscle tissue: Muscle tissue consists of muscle fibers and is classified into skeletal, cardiac, and smooth muscle, not squamous, cuboidal, or columnar.

C. Connective tissue: Connective tissue includes bone, blood, cartilage, and adipose tissue, none of which are classified as squamous, cuboidal, or columnar.

D. Epithelial tissue: Epithelial tissue consists of different cell shapes, including squamous (flat), cuboidal (cube-shaped), and columnar (tall and narrow), which line body surfaces and cavities.

A. Blistering: Blistering is characteristic of second-degree (partial-thickness) burns, not first-degree burns.

B. Leathery skin: Leathery or tough skin is a sign of a third-degree (full-thickness) burn, which extends through the dermis.

C. Waxy skin: Waxy, white, or charred skin is seen in deep burns, including third- and fourth-degree burns, not first-degree burns.

D. Erythema (redness): First-degree burns (superficial burns) affect only the epidermis and present as erythema, pain, and possible mild swelling without blistering.