A system that uses barriers between blood, all body fluids, nonintact skin, and mucous membranes of all individuals and susceptible people is called:

The correct answer is Standard Precautions. This term refers to a comprehensive set of infection control practices that prioritize the protection of healthcare workers and patients by minimizing the risk of transmission of pathogens.

Standard Precautions are designed to be applied to all patients, regardless of their diagnosis or presumed infection status. This system incorporates the use of barriers, which include gloves, masks, eye protection, and gowns, to protect against exposure to blood, bodily fluids, nonintact skin, and mucous membranes. By applying these precautions universally, the likelihood of spreading infections—whether from a patient who is known to be ill or from someone who is asymptomatic—is significantly reduced.

In contrast, while Universal Precautions specifically focused on bloodborne pathogens and were a predecessor to Standard Precautions, the latter encompasses a broader range of practices that include all potential sources of infection, not just those related to blood. Infection control is a more general term that describes the overarching strategies used to prevent and control infections, but it does not specifically define the particular system of barriers and practices utilized. The term "liner, nonthreshold" does not relate to infection control practices and is likely outside the scope of this context.