Carbon occurs as the native element in the earth's crust in the form of.

Options

A. diamond
B. methane
C. carbon dioxide
D. gas carbon.

Answer

**Step-by-Step Solution:**

1. **Understanding Native Carbon**: The question asks about the native forms of carbon found in the Earth's crust. Native elements are those that exist in their pure form in nature.

2. **Evaluating the Options**:
- **Diamond**: While diamond is a form of carbon, it is not found in the Earth's crust in its native state. Diamonds are formed under high pressure and temperature conditions from graphite.
- **Methane**: Methane (CH₄) is a compound made of carbon and hydrogen. It is not a native form of carbon because it requires a chemical reaction to form.
- **Carbon Dioxide**: Carbon dioxide (CO₂) is a gas that consists of carbon and oxygen. Like methane, it is not a native form of carbon and is produced through chemical reactions.
- **Gas Carbon**: This refers to carbon in its gaseous state, such as carbon vapor or soot. This can be considered a native form of carbon found in the Earth's crust.

3. **Conclusion**: Based on the evaluation of the options, the correct answer is that carbon occurs as the native element in the Earth's crust in the form of gas carbon.

**Final Answer**: Carbon occurs as the native element in the Earth's crust in the form of gas carbon.

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