Viruses are:

Viruses are primarily transmitted to food rather than grown in it, which distinguishes them from bacteria. When a virus comes into contact with food—often through contaminated water, inadequate hygiene practices, or infected food handlers—it can be ingested and cause illness. Unlike bacteria, which can multiply in food, viruses do not have the ability to grow or reproduce outside a host organism.

The other options incorrectly attribute characteristics or behaviors to viruses. For instance, viruses do not include bacteria like Salmonella and Shigella, which are pathogens that cause foodborne illnesses but are classified as bacteria, not viruses. Furthermore, while some microorganisms produce toxins, viruses themselves do not produce toxins; rather, they cause illness through their presence and ability to invade human cells. This understanding of virus transmission is crucial in food safety protocols and HACCP planning.