Thermocline is a constituent of

Options

A. Epilimnion
B. Metalimnion
C. Hypolimnion
D. None of the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Thermocline**: The thermocline is defined as a transition zone in a body of water, specifically between warmer surface waters and cooler deep waters. It is characterized by a rapid change in temperature with depth.

2. **Identifying the Layers**: In a stratified body of water, there are typically three layers:
- **Epilimnion**: The upper layer that is warm and directly exposed to sunlight.
- **Metalimnion**: The middle layer, also known as the thermocline, where the temperature decreases rapidly with depth.
- **Hypolimnion**: The bottom layer that is cold and not exposed to sunlight.

3. **Analyzing the Options**:
- **Option 1: Epilimnion** - This is the warm surface layer, not the thermocline.
- **Option 2: Metalimnion** - This is the correct answer, as it is the layer where the thermocline is located.
- **Option 3: Hypolimnion** - This is the cold bottom layer, not the thermocline.
- **Option 4: None of the above** - This is incorrect since the thermocline is indeed a part of one of the options.

4. **Conclusion**: Based on the definitions and characteristics of the layers, the thermocline is a constituent of the metalimnion.

**Final Answer**: The thermocline is a constituent of the metalimnion (Option 2).

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