Members of kingdom Protista are primarily

Options

A. parasites
B. terrestrial
C. aquatic
D. photosynthetic.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Kingdom Protista**: The question asks about the primary characteristics of members of the kingdom Protista. This kingdom is part of the five-kingdom classification system, which includes Monera, Fungi, Plantae, and Animalia.

2. **Characteristics of Protista**: Members of the kingdom Protista are primarily unicellular organisms. This means they consist of a single cell, which is a key feature of this kingdom.

3. **Habitat of Protista**: The majority of protists are aquatic, meaning they thrive in water environments. This includes both freshwater and marine (saltwater) habitats.

4. **Role of Water**: The aquatic nature of protists is essential because unicellular organisms require a medium (like water) for movement and nutrient absorption.

5. **Examples of Aquatic Protists**: Plankton, which are small organisms that drift in water, are a common example of protists. They play a significant role in aquatic ecosystems.

6. **Secondary Habitats**: While some protists can act as parasites in other organisms (including humans), this is not their primary habitat. Their primary habitat remains aquatic environments.

7. **Conclusion**: Based on the characteristics and habitats of members of the kingdom Protista, the correct answer to the question is that they are primarily aquatic.

**Final Answer**: Members of kingdom Protista are primarily aquatic.

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