Which of the following is considered a barrier product?

A barrier product is designed to create a protective layer on the skin or nails, helping to prevent moisture loss and protect against environmental factors. Nail creams fit this definition because they are formulated to hydrate and shield the nails and surrounding skin from damage and dryness. They typically contain ingredients that help lock in moisture, thus acting as a barrier against irritants.

Hand sanitizer and antiseptic solutions are primarily designed to clean and disinfect, targeting the removal of germs and bacteria rather than providing a protective barrier. Cuticle oil, while beneficial for nail health and moisture, serves more to nourish and soften the cuticles rather than acting as a protective layer. Therefore, nail creams stand out as the correct answer since they specifically function to provide a protective and moisturizing barrier.