Phytoplankton are dominant in

Options

A. limnetic zone
B. profundal zone
C. littoral zone
D. benthic zone

Answer

**Step-by-Step Solution:**

1. **Understanding Phytoplankton**: Phytoplankton are microscopic, floating microorganisms that are primarily found in aquatic environments. They are essential for the ecosystem as they perform photosynthesis and produce oxygen.

2. **Identifying the Habitat**: Phytoplankton thrive in areas where there is ample light because they require sunlight for photosynthesis. Therefore, their dominance is linked to zones with high light availability.

3. **Evaluating the Options**:
- **Option 1: Limnetic Zone**: This zone is characterized by being well-lit and open, making it a suitable habitat for phytoplankton. This is the correct answer.
- **Option 2: Profundal Zone**: This zone is deeper and receives less light, making it unsuitable for phytoplankton. Thus, this option is incorrect.
- **Option 3: Littoral Zone**: While this zone is near the shore, it is not primarily dominated by phytoplankton. It may have some presence, but it is not the dominant zone for them. Therefore, this option is incorrect.
- **Option 4: Benthos Zone**: This zone is at the bottom of the water body and is also not conducive for phytoplankton growth due to lack of light. Hence, this option is incorrect.

4. **Conclusion**: After evaluating all the options, it is clear that phytoplankton are dominant in the **limnetic zone**.

**Final Answer**: Phytoplankton are dominant in the **limnetic zone**.

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