Which statement about pathogens is true?

• A. They are a type of mold.
• B. They are microorganisms that cause illness.
• C. They are always visible to the eye.
• D. They are killed by refrigeration.

Answer: (B)

Pathogens are microorganisms that cause illness. This group includes bacteria, viruses, fungi, and parasites, all capable of making people sick. Many pathogens are microscopic and cannot be seen with the naked eye, which is why symptoms and lab tests are used to identify them rather than sight. While some pathogens can be molds, pathogens are not limited to molds; they encompass a much broader range of organisms. Refrigeration slows the growth of many pathogens but does not reliably kill them, and some can survive or remain infectious at cold temperatures. So the statement that pathogens are microorganisms that cause illness is accurate, while the other options don’t capture the full nature of pathogens.