Which of the following agents is primarily used to treat surfaces rather than skin?

The primary function of a disinfectant is to eliminate or inactivate harmful microorganisms on surfaces, making it distinct in its application from agents like antiseptics. Disinfectants are specifically formulated to be effective on non-living surfaces such as countertops, medical instruments, and floors, where the goal is to reduce the risk of infection or contamination.

In contrast, antiseptics are designed for use on skin and living tissue to prevent infection during surgeries or when caring for cuts and abrasions. While soaps and detergents can help remove dirt and oils, they do not necessarily possess the antimicrobial properties that disinfectants have. Thus, for the purpose of treating surfaces specifically, disinfectants are the correct choice.