The term pathogen is best described as what?

The term pathogen is best described as what?

• A. A virus
• B. A non-living particle
• C. A microorganism that causes disease
• D. A vaccine

Answer: (C)

Pathogens are disease-causing agents. They can be living microorganisms such as bacteria, fungi, and parasites, or infectious particles like viruses. The best description among the options is “a microorganism that causes disease” because it covers the idea that a pathogen is something that can cause illness and is an organism (in the common sense used in biology), not a vaccine and not limited to a non-living particle. While viruses blur the line between living and non-living outside a host, many pathogens are living organisms, so the broad phrase best captures the concept.

Pathogens are disease-causing agents. They can be living microorganisms such as bacteria, fungi, and parasites, or infectious particles like viruses. The best description among the options is “a microorganism that causes disease” because it covers the idea that a pathogen is something that can cause illness and is an organism (in the common sense used in biology), not a vaccine and not limited to a non-living particle. While viruses blur the line between living and non-living outside a host, many pathogens are living organisms, so the broad phrase best captures the concept.