The green house gas is:

Options

A. oxygen
B. nitrogen
C. chlorine
D. carbon dioxide

Answer

**Step-by-Step Solution:**

1. **Understanding Greenhouse Effect**: The greenhouse effect refers to the process by which certain gases in the Earth's atmosphere trap heat from the sun. This is similar to how a greenhouse works, where the glass walls trap heat inside to maintain a warm environment for plants.

2. **Identifying Greenhouse Gases**: Greenhouse gases include various gases that can absorb and emit infrared radiation. The most common greenhouse gases are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and water vapor (H2O).

3. **Analyzing the Options**: The question likely provides multiple-choice options. We need to identify which of these gases is a significant greenhouse gas.

4. **Evaluating Each Option**:
- **Oxygen (O2)**: While essential for life, oxygen does not significantly contribute to the greenhouse effect as it does not absorb infrared radiation.
- **Carbon Dioxide (CO2)**: This gas is a major contributor to the greenhouse effect, as it effectively traps heat in the atmosphere.
- **Other Options**: If other gases are listed, we would evaluate their contributions to the greenhouse effect as well.

5. **Conclusion**: Based on the analysis, carbon dioxide (CO2) is identified as the correct answer, as it is a major greenhouse gas that contributes significantly to the greenhouse effect.

**Final Answer**: The greenhouse gas is carbon dioxide (CO2).

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