Which gas is released during photosynthesis?

Options

A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Water vapour

Explanation

**Step-by-Step Solution:**

1. **Understanding Photosynthesis**: Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose (sugar). This process primarily occurs in the leaves of plants.

2. **Raw Materials for Photosynthesis**: The main raw materials used in photosynthesis are carbon dioxide (CO2) and water (H2O). These materials are absorbed by the plant.

3. **Role of Sunlight**: Sunlight is essential for photosynthesis. It provides the energy needed for the chemical reactions that convert carbon dioxide and water into glucose and oxygen.

4. **Chemical Reaction**: During photosynthesis, the following chemical reaction occurs:
\[ 6CO_2 + 6H_2O + \text{light energy} \rightarrow C_6H_{12}O_6 + 6O_2 \]
In this reaction, carbon dioxide and water are converted into glucose (C6H12O6) and oxygen (O2).

5. **Gas Released**: From the reaction, it is clear that oxygen is produced as a byproduct. This means that oxygen gas is released into the atmosphere during photosynthesis.

6. **Conclusion**: Therefore, the gas that is released during photosynthesis is oxygen.

**Final Answer**: Oxygen

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