For a scenario where a customer is viewing a product available in multiple color options and must select only one color for each product, radio buttons are the ideal UI control. Radio buttons allow all options to be presented to the user simultaneously, without the need for any additional action to view the choices. Importantly, they enforce a single selection, ensuring the user can only choose one of the available color options.

A. Radio buttons: This control type is specifically designed for cases where a single choice must be made out of multiple options presented. It is user-friendly and visually communicates that only one option can be selected, making it perfect for selecting a product color.

The other options, such as Text input (B), Drop-down (C), and Check box (D), do not fulfill the requirements as effectively. Text input doesn't provide predefined choices, a drop-down requires an additional click to view options, and check boxes allow multiple selections, which does not match the requirement of selecting only one option.