The type of infection transmission that is primarily spread on contaminated items, food, or water is called:

The correct answer is that this type of infection transmission is known as common vehicle transmission. This mode of transmission refers specifically to the spread of pathogens through contaminated items, food, or water, which serves as a vehicle for the infectious agent to reach a host.

In this context, the term "common vehicle" indicates that the same source can infect multiple individuals simultaneously, especially when a contaminated food item or water supply is consumed by a group of people. This is distinct from other modes of transmission, such as contact, airborne, or droplet transmission, which involve different mechanisms of spreading infections.

For instance, contact transmission typically involves direct or indirect contact between individuals or surfaces, while airborne transmission refers to the dispersion of infectious agents through the air over long distances. Droplet transmission involves larger respiratory droplets that travel short distances when a person coughs or sneezes. Each of these transmission routes operates differently than common vehicle transmission, which focuses on the role of contaminated substances in spreading disease.