The following is not an ozone depleting substace

Options

A. `H_(2) S`
B. CFCs
C. `NO_(X)`
D. Methane

Answer

To determine which of the following is not an ozone-depleting substance, we need to understand what ozone depletion is and which substances contribute to it.

### Step-by-Step Solution:

1. **Understanding Ozone Depletion**:
- Ozone depletion refers to the thinning of the ozone layer in the Earth's stratosphere, primarily caused by certain chemicals that break down ozone molecules.

2. **Identifying Ozone-Depleting Substances**:
- Common ozone-depleting substances include:
- Chlorofluorocarbons (CFCs)
- Hydrocarbons
- Nitrogen oxides (NOx)
- Hydrogen sulfide (H2S)

3. **Analyzing the Given Options**:
- **Option 1: Hydrogen sulfide (H2S)** - This is not primarily known for depleting ozone.
- **Option 2: CFCs** - These are well-known ozone-depleting substances.
- **Option 3: Nitrogen oxides (NOx)** - These can contribute to ozone depletion.
- **Option 4: Methane (CH4)** - While methane has some indirect effects on ozone, it is not classified as a direct ozone-depleting substance.

4. **Conclusion**:
- Among the options provided, **methane (Option 4)** is not considered an ozone-depleting substance.

### Final Answer:
The following is not an ozone-depleting substance: **Methane (Option 4)**.

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