What are the primary components of the hair structure?

• A. Shaft, root
• B. Shaft, root, follicle; hair layers include cuticle, cortex, and medulla
• C. Hair follicle only
• D. Cuticle, cortex, medulla

Answer: (B)

Hair structure comprises two main parts: the portion you can see—the shaft—and the portion below the surface—the root, which sits in a hair follicle. Inside the hair itself are three layers: the outer cuticle, the middle cortex, and the inner medulla. The follicle provides the environment and nourishment for growth. This option is best because it includes both the parts of the hair (shaft, root, and follicle) and the internal hair layers (cuticle, cortex, medulla). Other options miss essential elements: one lists only shaft and root, missing the follicle; another lists only the hair layers; another lists only the follicle.