Q. Phytoplankton are dominant in

Options

A. a) Limnetic zone
B. b) Profundal zone
C. c) Littoral zone
D. d) Benthic zone

Answer

**Step-by-Step Solution:**

1. **Understanding Phytoplankton**: Phytoplankton are microscopic, free-floating organisms that live in aquatic environments. They are primarily found in water bodies where they can photosynthesize.

2. **Identifying Water Zones**: The question presents four different zones: limnatic, profundal, littoral, and benthic. Each of these zones has distinct characteristics:
- **Limnatic Zone**: This zone refers to the open water area of a lake or pond, away from the shore. It is typically well-lit and supports a variety of aquatic life, including phytoplankton.
- **Profundal Zone**: This is the deeper part of a water body, where light penetration is minimal. It is not conducive for phytoplankton growth due to lack of sunlight.
- **Littoral Zone**: This zone is near the shore and is characterized by shallow waters. While it supports various aquatic plants and animals, it is not primarily dominated by phytoplankton.
- **Benthic Zone**: This refers to the bottom of the water body, where organisms live on or in the sediment. Phytoplankton do not thrive here as they require light and are not bottom-dwelling.

3. **Conclusion**: Given that phytoplankton are free-floating organisms that thrive in well-lit, open water, the limnatic zone is the most suitable habitat for them. Therefore, phytoplankton are dominant in the limnatic zone.

4. **Final Answer**: The correct option is **A. Limnatic Zone**.

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