Choose the correct answer :
In an ecosystem :

Options

A. Movement of energy is unidirectional
B. Energy cycling is an independent process
C. Energy cycling and nutrient cycling a coupled process
D. Micro and macronutrients cycle at same pace

Answer

**Step-by-Step Solution:**

1. **Understanding Energy Movement in Ecosystems:**
- In an ecosystem, energy flows in a unidirectional manner. This means that energy moves in one direction, from producers to consumers and then to decomposers.

2. **Energy Cycling vs. Nutrient Cycling:**
- Energy cycling is not a coupled process with nutrient cycling. While both processes are essential for ecosystem functioning, they operate independently. Nutrient cycling involves the recycling of nutrients through various organisms, while energy cycling does not recycle energy.

3. **Role of Decomposers:**
- Decomposers play a crucial role in nutrient cycling. They break down dead organic matter, returning nutrients to the soil, which can then be used by plants. However, they do not affect the unidirectional flow of energy.

4. **Pace of Nutrient Cycling:**
- The pace of micro and macronutrient cycling is different. Micro and macronutrients are cycled at different rates, primarily influenced by the activity of decomposers and environmental conditions.

5. **Trophic Levels:**
- Energy cycling is dependent on trophic levels. Each level of the food chain (producers, primary consumers, secondary consumers, etc.) plays a role in the transfer of energy. Without these levels, energy cycling would not occur.

6. **Conclusion:**
- Based on the above points, the correct answer to the question "In an ecosystem:" is that the movement of energy is unidirectional.

**Final Answer:**
- The correct answer is: **A) Movement of energy is unidirectional.**

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