Which of the following best describes Paramecium?

• A. A unicellular, ciliated protozoan commonly found in freshwater environments
• B. A multicellular fungus responsible for bread mold
• C. A non-enveloped DNA virus that infects bacteria
• D. A photosynthetic cyanobacterium found in marine ecosystems

Answer: (A)

Verified step by step guidance

1. Identify the nature of Paramecium by recalling its classification in microbiology. Paramecium is a genus of protozoa, which are single-celled eukaryotic organisms.
2. Understand the characteristics of Paramecium: it is unicellular, meaning it consists of a single cell, and it is covered with cilia, which are hair-like structures used for movement and feeding.
3. Recognize the typical habitat of Paramecium, which is freshwater environments such as ponds and lakes, where it plays a role in the microbial ecosystem.
4. Compare the options given: exclude multicellular fungi (which are not unicellular and do not have cilia), viruses (which are acellular and do not have cilia), and cyanobacteria (which are photosynthetic bacteria, not protozoa).
5. Conclude that the best description of Paramecium is 'A unicellular, ciliated protozoan commonly found in freshwater environments' based on its cellular structure, locomotion method, and habitat.