Which of the following products utilizes nanotechnology?

The multivitamin power exfoliant is the correct choice when discussing products that utilize nanotechnology. Nanotechnology involves manipulating materials on an atomic or molecular scale, often to enhance the delivery and effectiveness of ingredients in cosmetic formulations.

In the context of a multivitamin power exfoliant, nanotechnology can be employed to create more effective delivery systems for vitamins and exfoliating agents, allowing them to penetrate deeper into the skin or act more efficiently. This enhances the product's overall efficacy in promoting cell turnover and achieving smoother, brighter skin.

In contrast, the other options, while they may contain active ingredients beneficial for the skin, typically do not focus on or leverage nanotechnology in their formulation. Skin hydrating serums, aloe vera gels, and vitamin C essences may incorporate various proven ingredients but do not specifically emphasize the nanotechnology aspect.