The macronutrient______is a component of all organic compounds but is not obtained from soil.

Options

A. Carbon
B. hydrogen
C. oxygen
D. nitrogen

Explanation

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

### Step 1: Understand the Question
The question is asking for a macronutrient that is essential for organic compounds but is not sourced from the soil.

### Step 2: Identify the Macronutrients
The macronutrients typically include:
- Carbon
- Hydrogen
- Oxygen
- Nitrogen
- Phosphorus
- Potassium

### Step 3: Analyze Each Option
- **Carbon**: It is a fundamental component of all organic compounds and is the backbone of biomolecules like proteins, carbohydrates, and lipids. However, carbon is primarily obtained from the atmosphere (as carbon dioxide) and not from the soil.

- **Hydrogen**: This element is obtained from water, which plants absorb from the soil.

- **Oxygen**: While it is a component of organic compounds, oxygen is also obtained from water and the atmosphere.

- **Nitrogen**: This is absorbed from the soil in the form of nitrates and ammonium.

### Step 4: Conclusion
Since carbon is the only macronutrient that is a component of all organic compounds and is not obtained from the soil, the answer to the question is **Carbon**.

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

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