Which one of the following is not a non-biodegradable industrial waste?

Options

A. Gypsum from fertilizer industries
B. Mud and tailings from metal industries
C. Slag from stell industries
D. Waste from textile industries.

Answer

To solve the question "Which one of the following is not a non-biodegradable industrial waste?", we need to identify which option represents a biodegradable industrial waste. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Terms
- **Biodegradable**: Substances that can be decomposed naturally by microorganisms (like bacteria) into simpler, non-toxic substances.
- **Non-biodegradable**: Substances that cannot be decomposed naturally and remain in the environment for a long time.

### Step 2: Analyze Each Option
1. **Gypsum from fertilizer industries**: Gypsum is a mineral used in fertilizers and is considered non-biodegradable because it does not decompose easily in nature.

2. **Mud and tailings from metal industries**: Mud and tailings contain metals and toxic substances, making them non-biodegradable as they do not break down naturally.

3. **Slag from steel industries**: Slag is a byproduct of steel manufacturing and is also non-biodegradable as it does not decompose.

4. **Waste from textile industries**: This waste often includes materials derived from natural sources, such as cotton, which can be decomposed by microorganisms. Therefore, this is a biodegradable waste.

### Step 3: Identify the Correct Answer
Since we are looking for the option that is **not** a non-biodegradable industrial waste, we find that the waste from textile industries is biodegradable. Thus, it is the correct answer.

### Conclusion
The answer to the question is: **Waste from textile industries** (the fourth option).

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