Biogas production is a

Options

A. Three step microbial process
B. Three step physical process
C. Four step aerobic process
D. Four step anaerobic process

Answer

**Step-by-Step Solution:**

1. **Understanding Biogas Production**: Biogas is produced from organic waste materials. These materials can include agricultural waste, municipal waste, plant material, sewage, and kitchen waste.

2. **Role of Microorganisms**: The production of biogas involves microorganisms that break down the organic waste. This process occurs in the absence of oxygen, which is referred to as anaerobic conditions.

3. **Anaerobic Digestion**: The anaerobic digestion of organic waste takes place in a closed system. This means that the process is contained and does not allow oxygen to enter.

4. **Three Steps of Biogas Production**: The biogas production process consists of three main steps:
- **Hydrolysis**: The breakdown of complex organic materials into simpler compounds.
- **Acidification**: The conversion of these simpler compounds into organic acids.
- **Methane Formation**: The final step where methane, the primary component of biogas, is produced.

5. **Identifying the Correct Option**: Given the options:
- 3-step microbial process
- 3-step physical process
- 4-step aerobic process
- 4-step anaerobic process

The correct answer is the **3-step microbial process** because it accurately describes the nature of biogas production involving microorganisms in a three-step process.

**Final Answer**: Biogas production is a **3-step microbial process**.

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