Which group of microorganisms is unicellular, prokaryotic, has a cell wall, and often lives in extreme environments?

• A. Fungi
• B. Archaea
• C. Protozoa
• D. Algae

Answer: (B)

Verified step by step guidance

1. Identify the key characteristics given in the problem: unicellular, prokaryotic, has a cell wall, and often lives in extreme environments.
2. Recall that prokaryotic organisms lack a nucleus and membrane-bound organelles, which distinguishes them from eukaryotes like fungi, protozoa, and algae.
3. Understand that fungi, protozoa, and algae are generally eukaryotic, meaning they have a nucleus and more complex cell structures.
4. Recognize that Archaea are unicellular prokaryotes with cell walls and are known for thriving in extreme environments such as hot springs, salt lakes, and acidic conditions.
5. Conclude that the group matching all these criteria is Archaea, based on their cellular structure and ecological niche.