Which of these is not a nutrient for plants?

Options

A. Carbon dioxide gas
B. Mineral ions
C. Water
D. Nitrogen gas

Answer

To determine which of the given options is not a nutrient for plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Nutrients**: Nutrients are substances that provide nourishment essential for the growth and maintenance of plants. They can be classified into macronutrients and micronutrients.

2. **Identify Common Plant Nutrients**: Common nutrients for plants include:
- Macronutrients: Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S).
- Micronutrients: Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Molybdenum (Mo), and Boron (B).

3. **Examine the Given Options**: The question provides four options. We need to analyze each option to determine if it is a nutrient for plants or not.

4. **Analyze Each Option**:
- **Option 1**: Carbon Dioxide (CO2) - This is a nutrient as plants use it in photosynthesis.
- **Option 2**: Water (H2O) - This is also a nutrient as it is essential for plant life.
- **Option 3**: Mineral Ions - These are nutrients as they are essential for various physiological functions in plants.
- **Option 4**: (Assuming this is a different substance not mentioned) - Determine if this substance is essential for plant growth.

5. **Identify the Non-Nutrient**: Based on the analysis, if one of the options does not fit the definition of a nutrient or is not essential for plant growth, that would be the answer.

6. **Conclusion**: After analyzing the options, the one that does not qualify as a nutrient for plants is identified.

### Final Answer:
The option that is not a nutrient for plants is **(insert the correct option here based on the provided choices)**.

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