What is the main function of nails?

The primary function of nails is protection. Nails serve to protect the sensitive tips of fingers and toes from injury, allowing us to perform daily tasks without causing harm to the underlying tissues. They also provide a framework that enhances the ability to grasp and manipulate objects. The hard keratin structure of nails makes them durable and well-suited to fulfill this protective role effectively.

While nails may have aesthetic value and can be used for decoration, that is a secondary aspect and not their main function. Chemical storage and weight bearing are not relevant functions of nails; they do not store significant amounts of chemicals or support the body's weight in any biological way. Hence, the correct answer emphasizes nails' fundamental role in safeguarding the delicate areas they cover.