In deep fresh water ponds, different layers of water with different temperatures are noticed,This is known as

Options

A. Thermal stratification
B. Surface tension
C. Water equilibrium
D. Thermal equilibrium.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the phenomenon observed in deep freshwater ponds where different layers of water have varying temperatures.

2. **Identifying the Options**: The options provided are:
- A) Thermal Stratification
- B) Surface Tension
- C) Water Equilibrium
- D) Thermal Equilibrium

3. **Defining Thermal Stratification**: Thermal stratification refers to the layering of water in a body of water, where warmer water is found on top and colder water is found below. This occurs due to differences in water density, which is affected by temperature.

4. **Explaining the Layers**: In deep freshwater ponds, the upper layer is called the epilimnion (warm water) and the lower layer is called the hypolimnion (cold water). The cold water is denser and settles at the bottom, while the warmer water is less dense and stays on the surface.

5. **Conclusion**: Based on the definitions and explanations, the correct answer to the question is **A) Thermal Stratification**.

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