Which one of the following pairs of gases are the major cause of "Greenhouse effect" ?

Options

A. `CO_(2)` and `O_(3)`
B. `CO_(2)` and `CO`
C. `CFCs` and `SO_(2)`
D. `CO_(2)` and `N_(2)O`

Explanation

To determine which pair of gases is the major cause of the greenhouse effect, we can follow these steps:

### Step 1: Understand the Greenhouse Effect
The greenhouse effect is a natural process that warms the Earth’s surface. It occurs when the sun's energy reaches the Earth and some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases.

### Step 2: Identify Greenhouse Gases
The primary greenhouse gases include:
- Carbon Dioxide (CO2)
- Methane (CH4)
- Nitrous Oxide (N2O)
- Chlorofluorocarbons (CFCs)

### Step 3: Analyze the Options
Now, let's analyze the given options:
1. **CO2 and O3**: Ozone (O3) is not a significant greenhouse gas.
2. **CO2 and CO**: Carbon Monoxide (CO) is not a greenhouse gas.
3. **CFC and SO2**: Sulfur Dioxide (SO2) is not a greenhouse gas, although CFCs are.
4. **CO2 and N2O**: Both Carbon Dioxide (CO2) and Nitrous Oxide (N2O) are greenhouse gases.

### Step 4: Conclusion
After analyzing all the options, the correct pair of gases that are the major cause of the greenhouse effect is **CO2 and N2O**.

### Final Answer
The correct answer is **Option 4: CO2 and N2O**.

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