Which of the following features can be added to prescription lenses at Costco?

Anti-reflective coating is a common feature that can be added to prescription lenses at Costco. This coating enhances the performance and appearance of the lenses by reducing glare from screens and bright lights, improving clarity and vision comfort. It also helps to make the lenses look more transparent, as it diminishes the reflections that can distract from the wearer's eyes. Additionally, this coating can improve night vision for individuals who drive after dark, as it reduces halos around lights.

Digital frame fitting and waterproof coating aren't standard features typically added to prescription lenses, and while UV color-changing lenses, like photochromic lenses, are available, they differ from the common anti-reflective option in terms of functionality and application. Therefore, the ability to add an anti-reflective coating is a key feature offered by Costco that enhances the overall user experience with prescription lenses.