Which statement correctly lists the three main parts of a hair strand?

• A. Cuticle, Cortex, and Medulla
• B. Cortex, Medulla, and Cuticle
• C. Medulla, Cuticle, and Cortex
• D. Cuticle, Medulla, and Cortex

Answer: (A)

The outermost layer of a hair strand is the cuticle, a protective coating made of overlapping scale-like cells. Beneath it lies the cortex, the thick middle layer that provides most of the hair’s strength, elasticity, and color due to its keratin fibers and pigment. The innermost layer is the medulla, the central core that can be present as loosely packed cells or air spaces; some fine hairs may not have a medulla at all. The statement that lists the three parts from outside to inside—cuticle, cortex, and medulla—matches how a hair is actually built, which is why it’s the correct choice. Other sequences mix these layers, which doesn’t reflect their true arrangement inside the strand.