Which of the following is a function of the skin?

The skin serves multiple essential functions, making the choice of “All of the above” the most comprehensive answer.

Secretion is one of the critical roles of the skin, as it produces sweat and oils through various glands. These secretions help regulate body temperature and maintain skin hydration.

Absorption is also a significant function, as the skin can absorb certain substances, including medications, topical applications, and some harmful substances. This ability is vital in various medical and cosmetic applications, such as transdermal drug delivery systems.

Protection is perhaps the most recognized role of the skin. It acts as a barrier against environmental factors, including pathogens, chemicals, and physical injuries. The skin is the first line of defense in the immune system, preventing the entry of harmful microorganisms and providing a protective layer that helps to minimize injury.

Therefore, since the skin is responsible for secretion, absorption, and protection, it encompasses all of these functions, affirming that "All of the above" is indeed the correct answer.