Q. Which among the following is a disease-causing microorganism?

Correct Answer: b) Pathogens

Explanation:

A disease-causing microorganism is referred to as a pathogen. Pathogens are agents, such as bacteria, viruses, fungi, or protozoa, that can cause diseases in humans, animals, or plants. While some bacteria and protozoa can be pathogens, not all of them are harmful. For example, many bacteria are beneficial and play essential roles in processes like digestion and nutrient cycling.

On the other hand:

– Archaea are microorganisms that are generally not known to cause diseases in humans. They are often found in extreme environments and are not pathogenic.

– Bacteria can be either beneficial or harmful. Only certain types of bacteria are pathogens.

– Protozoa are single-celled organisms, and while some can cause diseases (e.g., malaria caused by Plasmodium), not all protozoa are harmful.