The substance that imparts green colour to the plants is known as

Options

A. Water
B. Chlorophyll
C. Carbon dioxide
D. Calcium.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the substance that gives plants their green color.

2. **Identifying the Options**: The options provided are:
- Water
- Chlorophyll
- Carbon Dioxide
- Calcium

3. **Analyzing Each Option**:
- **Water**: While water is essential for plant growth and various functions, it does not impart color to plants.
- **Chlorophyll**: This is a green pigment found in plants. It is responsible for the green color and plays a crucial role in photosynthesis by trapping sunlight.
- **Carbon Dioxide**: This gas is used by plants to make food but does not contribute to their color.
- **Calcium**: This is a nutrient that supports plant growth but is not responsible for the green color.

4. **Conclusion**: Based on the analysis, the substance that imparts green color to the plants is **Chlorophyll**.

5. **Final Answer**: The correct answer is **Chlorophyll**.

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