Which of the following is NOT listed as a category of infectious disease pathogens?

Which of the following is NOT listed as a category of infectious disease pathogens?

• A. Protozoa
• B. Bacteria
• C. Virus
• D. Fungi

Answer: (A)

Infectious disease pathogens are commonly grouped into several major categories, with bacteria, viruses, and fungi appearing as the primary groups in many introductory references. Protozoa, while capable of causing disease, are not always listed as a separate standard category in these quick-reference outlines. In this question’s framing, protozoa is the item not listed among the core pathogen categories, so it best fits as the one that isn’t included. The other groups—bacteria, viruses, and fungi—are widely recognized as the main categories of infectious disease pathogens, which is why they would appear in such a listing.

Infectious disease pathogens are commonly grouped into several major categories, with bacteria, viruses, and fungi appearing as the primary groups in many introductory references. Protozoa, while capable of causing disease, are not always listed as a separate standard category in these quick-reference outlines. In this question’s framing, protozoa is the item not listed among the core pathogen categories, so it best fits as the one that isn’t included. The other groups—bacteria, viruses, and fungi—are widely recognized as the main categories of infectious disease pathogens, which is why they would appear in such a listing.