Which of the following best describes an antiseptic?

An antiseptic is best described as a compound that inhibits the growth of microorganisms. This means that antiseptics reduce the number of bacteria and other pathogens on skin or surfaces, preventing infection and disease transmission without necessarily eliminating all microorganisms.

Understanding the term "inhibit" is key; while antiseptics do not kill all pathogens outright, they are effective at preventing their proliferation and helping to control infections. Therefore, antiseptics are commonly used in clinical settings to prepare skin before procedures and to clean wounds.

In contrast, the other options suggest either complete elimination of all pathogens or use in sterilization processes, which are not the primary functions of antiseptics. A sterilizing agent, for example, is specifically designed to kill all forms of microorganisms, and a cleanser for skin refers to products that clean but may not necessarily have any antimicrobial properties. Similarly, a compound that kills all pathogens is more accurately termed a disinfectant rather than an antiseptic.