In Whittaker's five kingdom classification, unicellular eukaryotes, primarily aquatic and various cell organelles constitute

Options

A. Monera
B. Protista
C. Animalia
D. Plantae

Answer

**Step-by-Step Solution:**

1. **Understanding Whittaker's Classification**: Robert H. Whittaker proposed a five-kingdom classification system to categorize all living organisms. The five kingdoms are Monera, Protista, Fungi, Plantae, and Animalia.

2. **Identifying Unicellular Eukaryotes**: The question specifies unicellular eukaryotes. Eukaryotic organisms are characterized by having a defined nucleus and various cell organelles.

3. **Aquatic Habitat**: The question mentions that these unicellular eukaryotes are primarily aquatic. This means they are mostly found in water bodies, which is a characteristic of certain groups of organisms.

4. **Kingdom Protista**: In Whittaker's classification, the kingdom that includes unicellular eukaryotes is Protista. This kingdom is known for containing simple, single-celled organisms that possess well-developed cell organelles.

5. **Conclusion**: Therefore, based on the characteristics mentioned in the question (unicellular, eukaryotic, primarily aquatic), the correct answer is the kingdom **Protista**.

**Final Answer**: Protista

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