Carbon becomes available to crop plants in the form of

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks in what form carbon becomes available to crop plants. We need to analyze the options provided to find the correct one.

2. **Analyzing the Options**:
- **Amino Acids**: While amino acids contain carbon, hydrogen, and oxygen, plants do not absorb them directly. Instead, plants synthesize amino acids using their own metabolic processes.
- **Carbonates**: Carbonates do contain carbon, but they are not the primary source of carbon for plants. They are absorbed but do not provide carbon in a usable form for photosynthesis.
- **Carbon Dioxide**: This is a gas that plants absorb from the atmosphere. It is essential for photosynthesis, where plants convert carbon dioxide into carbohydrates, which serve as their energy source.
- **Element Carbon**: Plants cannot utilize elemental carbon directly. They require carbon to be in a compound form, such as carbon dioxide.

3. **Identifying the Correct Answer**: Among the options, carbon dioxide is the only form that is directly used by plants for photosynthesis. Therefore, the correct answer is **carbon dioxide**.

4. **Conclusion**: The form in which carbon becomes available to crop plants is **carbon dioxide**.

**Final Answer**: Carbon becomes available to crop plants in the form of **carbon dioxide**.

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