The 'global warming' is mainly due to which gas?

Options

A. `N_(2)O`
B. `O_(2)`
C. `CO`
D. `CO_(2)`

Explanation

### Step-by-Step Text Solution:

1. **Understanding Global Warming**: Global warming refers to the increase in Earth's average surface temperature due to rising levels of greenhouse gases in the atmosphere.

2. **Identifying Greenhouse Gases**: Several gases contribute to global warming, including carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and chlorofluorocarbons (CFCs).

3. **Role of Carbon Dioxide**: Among these gases, carbon dioxide is the most significant contributor to global warming. It is released in large quantities from various human activities, particularly from burning fossil fuels in vehicles, industries, and power plants.

4. **Impact of Carbon Dioxide**: The large amount of carbon dioxide in the atmosphere traps heat, leading to an increase in the Earth’s temperature. This phenomenon is known as the greenhouse effect.

5. **Conclusion**: Given the options and the analysis, the main gas responsible for global warming is carbon dioxide (CO₂).

### Final Answer:
The main gas responsible for global warming is Carbon Dioxide (CO₂).

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