Open water zone in a deep lake/sea is called

Options

A. Littoral zone
B. Limnetic zone
C. Profundal zone
D. Disphotic zone.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes the "open water zone" in a deep lake or sea.

2. **Identifying the Options**: The options provided are:
- Option 1: Littoral zone
- Option 2: Limnetic zone
- Option 3: Profundal zone
- Option 4: Dysphotic zone

3. **Analyzing Each Option**:
- **Littoral Zone**: This is the area near the shore of a lake or pond. It consists of shallow waters where sunlight penetrates, allowing aquatic plants to grow. This zone is not the open water zone, so it is incorrect.

- **Limnetic Zone**: This zone is characterized as the open water area of a lake or pond. It is typically where sunlight can penetrate and supports a variety of aquatic life. This is the correct answer.

- **Profundal Zone**: This zone is located below the limnetic zone and is characterized by deeper waters where sunlight does not penetrate. It is not the open water zone, making it incorrect.

- **Dysphotic Zone**: Also known as the twilight zone, this is the layer of the ocean that receives only faint filtered sunlight. It is not the open water zone, so this option is also incorrect.

4. **Conclusion**: After analyzing all options, the correct answer is **Option 2: Limnetic zone**. This zone represents the open water area in a deep lake or sea.