True or False: Nails are made primarily of keratin.

Nails are primarily composed of a protein called keratin, which is a key structural component not only of nails but also of hair and the outer layer of skin. Keratin's role in nails provides durability and resistance, allowing them to protect the tips of fingers and toes. This fundamental aspect of nails being made of keratin holds true across all individuals, regardless of specific conditions or factors such as age. Thus, the answer is true, confirming the scientific understanding of the composition of nails.