Question

what are nails primarily made of? bone tissue collagen fibers epidermal tissue keratinized cells

Explanation:

Nails are part of the integumentary system. They are formed from keratinized cells. Keratin is a tough protein that provides strength and protection. As new cells are produced in the nail matrix (the area under the cuticle), older cells are pushed forward and become keratinized (filled with keratin), forming the hard nail structure. Bone tissue is related to bones, collagen fibers are in connective tissues like tendons and ligaments, and epidermal tissue is the outer layer of skin but not the main component of nails in the way keratinized cells are.

Answer:

Keratinized cells