Which of the following is not green house gas ?

Options

A. `CO_(2)`
B. `CH_(4)`
C. Chloro fluoro carbons
D. `O_(2)`

Answer

To determine which of the following is not a greenhouse gas, we need to identify the gases that contribute to the greenhouse effect. Here’s a step-by-step solution:

### Step 1: Understand Greenhouse Gases
Greenhouse gases are those gases in the Earth's atmosphere that trap heat. They allow sunlight to enter but prevent some of the heat that the sunlight brings from leaving the atmosphere. This process is known as the greenhouse effect.

### Step 2: Identify Common Greenhouse Gases
Some common greenhouse gases include:
- Carbon Dioxide (CO2)
- Methane (CH4)
- Nitrous Oxides (N2O)
- Water Vapour (H2O)
- Ozone (O3)
- Chlorofluorocarbons (CFCs)

### Step 3: Analyze the Options
Given the options, we need to check which one is not a greenhouse gas. The options provided are:
1. Carbon Dioxide (CO2)
2. Methane (CH4)
3. Chlorofluorocarbons (CFCs)
4. Oxygen (O2)

### Step 4: Determine the Non-Greenhouse Gas
- **Carbon Dioxide (CO2)**: Greenhouse gas
- **Methane (CH4)**: Greenhouse gas
- **Chlorofluorocarbons (CFCs)**: Greenhouse gas
- **Oxygen (O2)**: Not a greenhouse gas

### Conclusion
Oxygen (O2) is not a greenhouse gas as it does not contribute to the greenhouse effect or global warming. Therefore, the answer is:

**Oxygen (O2)** is not a greenhouse gas.

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