The sebaceous glands produce sebum, a material that:

The sebaceous glands are responsible for producing sebum, an oily substance that plays a crucial role in maintaining skin health. Sebum serves to waterproof the skin, preventing excessive water loss which is essential for overall hydration. This oil-based secretion helps to keep the skin supple by providing moisture and natural lubrication, thereby preventing it from becoming dry and cracked.

In addition to its waterproofing properties, sebum has antimicrobial qualities that can help to protect against bacterial growth on the skin. This dual function of keeping the skin hydrated and providing a barrier against pathogens is vital for maintaining the integrity of the skin and overall skin health. Therefore, the correct answer highlights the important role of sebum in both waterproofing the skin and maintaining its suppleness.