During sewage treatment, biogases are produced which include

Options

A. Methane, hydrogen sulphide, carbon dioxide
B. Methane, oxygen, hydrogen sulphide
C. Hydrogen sulphide, methane, sulphur dioxide
D. Hydrogen sulphide, nitrogen, methane

Answer

**Step-by-Step Solution:**

1. **Understanding Sewage Treatment**: Sewage treatment involves the process of removing contaminants from wastewater, which includes both primary and secondary treatment methods.

2. **Identifying Biogases Produced**: During the sewage treatment process, various biogases are produced as a result of the breakdown of organic matter by microorganisms.

3. **Listing the Gases**: The primary biogases produced during sewage treatment include:
- Methane (CH₄)
- Hydrogen Sulfide (H₂S)
- Carbon Dioxide (CO₂)

4. **Evaluating the Options**:
- **Option 1**: Methane, Hydrogen Sulfide, Carbon Dioxide – This option includes all the correct gases produced during sewage treatment.
- **Option 2**: Methane, Oxygen, Hydrogen Sulfide – This option is incorrect because oxygen is not produced during sewage treatment; it is produced during photosynthesis.
- **Option 3**: Hydrogen Sulfide, Methane, Sulfur Dioxide – This option is incorrect because sulfur dioxide is not produced during sewage treatment.
- **Option 4**: Hydrogen Sulfide, Nitrogen, Methane – This option is incorrect because nitrogen is not a product of sewage treatment.

5. **Conclusion**: The correct answer is **Option 1: Methane, Hydrogen Sulfide, Carbon Dioxide**.

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