Which step is not involved in the carbon-cycle ?

Options

A. Photosynthesis
B. Transpiration
C. Respiration
D. Burning of fossil fuels

Explanation

**Step-by-Step Solution:**

1. **Understanding the Carbon Cycle:** The carbon cycle is a natural process where carbon is exchanged among the atmosphere, land, water, and living organisms. Key processes in the carbon cycle include photosynthesis, respiration, and the burning of fossil fuels.

2. **Identifying the Steps:**
- **Photosynthesis:** Plants absorb carbon dioxide (CO2) from the atmosphere and convert it into glucose and oxygen using sunlight. This process is crucial for the carbon cycle as it incorporates carbon into living organisms.
- **Respiration:** Living organisms, including plants and animals, take in oxygen and release carbon dioxide back into the atmosphere as a byproduct of metabolism. This process also plays a significant role in the carbon cycle.
- **Burning of Fossil Fuels:** When fossil fuels are burned for energy, they release carbon dioxide and other carbon compounds into the atmosphere, contributing to the carbon cycle and affecting climate change.

3. **Analyzing Transpiration:** Transpiration is the process by which plants lose water vapor through small openings called stomata. While it is an essential process for plant health and water regulation, it does not involve the exchange of carbon in the same way as photosynthesis, respiration, or the burning of fossil fuels.

4. **Conclusion:** Since transpiration does not involve carbon exchange, it is the step that is not involved in the carbon cycle.

**Final Answer:** Transpiration is not involved in the carbon cycle.

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