One of the greenhouse gas is

Options

A. CO
B. `O_(2)`
C. `H_(2)`
D. CFC's

Answer

To determine which of the given options is a greenhouse gas, we will analyze each option based on the definition and examples of greenhouse gases.

### Step-by-Step Solution:

1. **Understanding Greenhouse Gases**:
- Greenhouse gases are substances that trap heat in the atmosphere, contributing to the greenhouse effect. This effect is crucial for maintaining the Earth's temperature.

2. **Identifying the Options**:
- The options provided are:
- A) Seawater (CO)
- B) Oxygen (O2)
- C) Hydrogen (H2)
- D) Chlorofluorocarbons (CFCs)

3. **Analyzing Each Option**:
- **Option A: Seawater (CO)**:
- Seawater is primarily composed of water (H2O) and does not function as a greenhouse gas. Carbon monoxide (CO) is not a significant greenhouse gas either.
- **Option B: Oxygen (O2)**:
- Oxygen is essential for life but does not trap heat in the atmosphere, making it not a greenhouse gas.
- **Option C: Hydrogen (H2)**:
- Hydrogen is a light gas and does not contribute to the greenhouse effect, so it is not a greenhouse gas.
- **Option D: Chlorofluorocarbons (CFCs)**:
- CFCs are synthetic compounds known to trap heat in the atmosphere and are recognized as greenhouse gases.

4. **Conclusion**:
- Among the options, the only greenhouse gas is **Option D: CFCs**.

### Final Answer:
One of the greenhouse gases is **CFCs (Chlorofluorocarbons)**.

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