Which nutrient is not involved directly with glutathione's ability to recycle antioxidants?

Glutathione plays a crucial role in the body’s antioxidant defense system, particularly in recycling other antioxidants and preventing oxidative stress. Among the nutrients mentioned, Vitamin C is well-known for its ability to be recycled by glutathione, as it works synergistically with glutathione to enhance the body's antioxidant capacity. Similarly, Vitamin E is also dependent on glutathione for its regeneration after it neutralizes free radicals.

Vitamin A, while essential for many bodily functions such as vision and immune response, does not have a direct interaction in the recycling process of antioxidants through glutathione. Selenium, on the other hand, is an important trace mineral that contributes to the activity of various antioxidant enzymes, including glutathione peroxidase, thereby playing an indirect role in the antioxidant defense.

Thus, among the nutrients listed, Vitamin A does not have a direct involvement in glutathione's recycling process of other antioxidants, making it the correct choice.