Which glands are responsible for lubricating the skin and preserving the softness of the hair?

Sebaceous glands are responsible for lubricating the skin and preserving the softness of the hair. These glands are located in the dermis layer of the skin and secrete an oily substance known as sebum. Sebum plays a critical role in maintaining the moisture balance of the skin and hair, creating a barrier that helps to protect against environmental damage and dehydration. The presence of sebum helps to prevent the hair from becoming dry and brittle, allowing it to retain its natural shine and texture.

In contrast, sweat glands are primarily involved in thermoregulation and excreting waste products, whereas salivary glands are responsible for producing saliva to aid in digestion. Endocrine glands secrete hormones into the bloodstream and are not directly involved in lubricating the skin or hair. Thus, sebaceous glands are uniquely suited for this specific function, making them the correct choice in the context of skin and hair health.