Which of the following acts as a green house gas ?

Options

A. `CO_(2)`
B. `O_(2)`
C. Ar
D. `CH_(4)`

Answer

To determine which of the following acts as a greenhouse gas, we can follow these steps:

### Step 1: Understand Greenhouse Gases
Greenhouse gases are substances that trap heat in the atmosphere, contributing to the greenhouse effect. This effect is essential for maintaining the Earth's temperature but can lead to global warming when concentrations of these gases increase.

### Step 2: Identify Common Greenhouse Gases
The most common greenhouse gases include:
- Water vapor (H2O)
- Carbon dioxide (CO2)
- Methane (CH4)
- Ozone (O3)
- Nitrous oxide (N2O)

### Step 3: Analyze the Options
If the question provides a list of gases, we need to check which of them are recognized as greenhouse gases.

### Step 4: Evaluate Each Gas
- **Carbon Dioxide (CO2)**: Yes, it is a significant greenhouse gas, contributing about 81% to the greenhouse effect.
- **Methane (CH4)**: Yes, it is also a greenhouse gas, contributing around 10%.
- **Oxygen (O2)**: No, it is not a greenhouse gas.
- **Argon (Ar)**: No, it is an inert gas and does not contribute to the greenhouse effect.

### Step 5: Conclusion
Based on the analysis, the gases that act as greenhouse gases from the options provided are:
- Carbon Dioxide (CO2)
- Methane (CH4)

### Final Answer
The greenhouse gases among the options are Carbon Dioxide (CO2) and Methane (CH4).

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