How many essential elements are called non-mineral elements?

Options

A. 3
B. 5
C. 7
D. 9

Answer

To answer the question "How many essential elements are called non-mineral elements?", we can follow these steps:

### Step-by-Step Solution:

1. **Define Essential Elements**: Essential elements are those elements that are necessary for the growth and reproduction of plants.

2. **Categorize Essential Elements**: Essential elements can be divided into two categories: mineral elements and non-mineral elements.

3. **Identify Mineral Elements**: Mineral elements are those that are obtained from the soil or the earth's crust.

4. **Identify Non-Mineral Elements**: Non-mineral elements, on the other hand, are obtained from the atmosphere, specifically from air and water.

5. **List Non-Mineral Elements**: The common non-mineral elements essential for plant growth include:
- Carbon (C) - obtained from carbon dioxide (CO2) in the air.
- Oxygen (O) - obtained from both air and water.
- Hydrogen (H) - obtained from water (H2O).

6. **Count Non-Mineral Elements**: From the list, we can see that there are three non-mineral elements: carbon, oxygen, and hydrogen.

7. **Conclusion**: Therefore, the number of essential elements that are classified as non-mineral elements is 3.

### Final Answer:
The number of essential elements called non-mineral elements is **3**.

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