Which of the following best describes a microbe?

• A. A type of plant cell found in leaves
• B. A microscopic organism, such as bacteria, viruses, fungi, or protozoa
• C. A non-living chemical compound
• D. A multicellular organism visible to the naked eye

Answer: (B)

Verified step by step guidance

1. Understand the definition of a microbe: Microbes are organisms that are typically too small to be seen with the naked eye and require a microscope for observation.
2. Identify the types of microbes: Common examples include bacteria, viruses, fungi, and protozoa, all of which are microscopic organisms.
3. Eliminate incorrect options: A plant cell found in leaves is not a microbe because it is part of a multicellular organism and usually visible under a light microscope but is not itself a microbe; a non-living chemical compound is not an organism at all; and a multicellular organism visible to the naked eye is not microscopic.
4. Recognize that microbes can be living organisms (like bacteria and fungi) or non-living infectious agents (like viruses), but all share the characteristic of being microscopic.
5. Conclude that the best description of a microbe is 'a microscopic organism, such as bacteria, viruses, fungi, or protozoa.'