A macronutrient which is component of all organic compounds but is not obtained from soil is

Options

A. N
B. P
C. Mg
D. C

Answer

To solve the question, "A macronutrient which is a component of all organic compounds but is not obtained from soil is," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Macronutrients**: The question asks for a macronutrient. Macronutrients include nitrogen, phosphorus, magnesium, and carbon.

2. **Analyze Each Option**:
- **Nitrogen**: Nitrogen is a macronutrient that is essential for plant growth and is found in the soil in the form of nitrates and nitrites.
- **Phosphorus**: Phosphorus is another macronutrient that is present in soil, primarily in the form of phosphates.
- **Magnesium**: Magnesium is also found in the soil as a divalent cation and is essential for photosynthesis.
- **Carbon**: Carbon is a fundamental element in all organic compounds. However, it is not directly obtained from the soil. Instead, carbon is part of the atmosphere and is incorporated into organic compounds through processes like photosynthesis.

3. **Conclusion**: Since nitrogen, phosphorus, and magnesium are all obtained from the soil, the only macronutrient that is a component of all organic compounds but is not obtained from the soil is carbon.

### Final Answer:
The macronutrient which is a component of all organic compounds but is not obtained from soil is **carbon**.

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