Which of the following substances is primarily used to kill pathogens on equipment?

The correct answer is that disinfectants are primarily used to kill pathogens on equipment. Disinfectants are chemical agents specifically formulated to eliminate bacteria, viruses, and fungi on inanimate objects and surfaces. They are typically used in medical settings, laboratories, and various industrial environments where maintaining a sterile condition is crucial for preventing the spread of infections and ensuring safety.

Antiseptics, while effective in reducing or preventing infection by inhibiting the growth of pathogens on living tissues (like skin), are not designed for use on equipment. Antibiotics are medications used to treat infections by targeting bacteria within the body and are not applicable for use on surfaces or equipment.

In summary, disinfectants play a critical role in sterilization processes by directly targeting and killing pathogens on equipment, making them the most appropriate choice in this context.