Spent slurry produced after producing gobar gas is :

Options

A. useless residue
B. used as a fuel after drying it
C. used as manure
D. used as food by animals

Answer

**Step-by-Step Solution:**

1. **Understanding Spent Slurry**: Spent slurry is the byproduct obtained after the production of gobar gas (biogas) from organic materials like cow dung. It consists of undigested organic matter and nutrients.

2. **Evaluating the Options**:
- **Option A: Useless Residue**: This suggests that spent slurry has no value, which is incorrect as it can be utilized in various ways.
- **Option B: Used as Fuel After Drying**: While dried slurry can be used as a fuel, it is not the primary use of spent slurry.
- **Option C: Used as Manure**: Spent slurry is rich in nutrients and is often used as organic manure for plants, making this a strong candidate.
- **Option D: Used as Food by Animals**: Spent slurry is not typically used directly as food for animals.

3. **Identifying the Correct Answer**: Among the options, the most appropriate use of spent slurry after producing gobar gas is as manure. It provides essential nutrients to the soil, enhancing plant growth.

4. **Conclusion**: Therefore, the correct answer is that the spent slurry produced after producing gobar gas is used as manure.

**Final Answer**: Used as manure.

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