Carbon becomes available to crop plants in the form of

Options

A. amino acids
B. carbonates
C. carbon dioxide
D. element carbon

Answer

To answer the question "Carbon becomes available to crop plants in the form of," we will analyze the options provided and determine the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding Carbon Sources for Plants**:
- Plants require carbon for their growth and development. The primary source of carbon for plants is through the process of photosynthesis.

2. **Evaluating the Options**:
- **A. Amino acid**: While amino acids contain carbon, they are not the primary form in which carbon is available to plants. Amino acids are produced after the plant has already utilized carbon.
- **B. Carbonates**: Carbonates are compounds that contain carbon, but they are not directly used by plants as a source of carbon for photosynthesis.
- **C. Carbon dioxide**: This is the gas that plants absorb from the atmosphere through small openings called stomata. During photosynthesis, carbon dioxide is converted into glucose, a carbohydrate.
- **D. Element carbon**: Elemental carbon is not in a form that plants can utilize directly. Plants cannot absorb solid carbon.

3. **Identifying the Correct Answer**:
- The only option that represents the form in which carbon is available to plants for photosynthesis is **C. Carbon dioxide**. This gas is essential for the photosynthetic process, where it is converted into organic compounds.

4. **Conclusion**:
- Therefore, the correct answer to the question is **C. Carbon dioxide**.