Plants purify air during

Options

A. Photosynthesis
B. Respiration
C. Transpiration
D. Desiccation.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks during which process plants purify the air. The options provided are photosynthesis, respiration, transpiration, and desiccation.

2. **Analyzing Photosynthesis:**
- Photosynthesis is the process by which plants convert carbon dioxide and water into glucose and oxygen using sunlight.
- During this process, oxygen is released as a by-product.

3. **Analyzing Respiration:**
- Respiration is the process where plants (and animals) consume oxygen and release carbon dioxide.
- This process does not purify the air; instead, it adds carbon dioxide to it.

4. **Analyzing Transpiration:**
- Transpiration is the process of water vapor loss from plant leaves.
- While it plays a role in water regulation, it does not involve the purification of air.

5. **Analyzing Desiccation:**
- Desiccation refers to the removal of moisture from the environment or an organism.
- This process does not relate to air purification.

6. **Conclusion:**
- Since photosynthesis is the only process among the options that results in the release of oxygen, which purifies the air, the correct answer is photosynthesis.

**Final Answer:** Plants purify air during photosynthesis.

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