the process of conversion of nitrogen to ammonia by microbes is

Options

A. nitrification
B. denitrification
C. nitrogen-fixation
D. Haber's process

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the process by which nitrogen is converted to ammonia by microbes.

2. **Analyzing the Options**:
- **Nitrification**: This is a microbial process where reduced nitrogen compounds are oxidized to nitrite and nitrate. This process does not involve the conversion of nitrogen gas (N₂) to ammonia (NH₃), so this option is incorrect.

- **Denitrification**: This process involves the reduction of nitrates (NO₃⁻) to molecular nitrogen (N₂) by microbes. It essentially removes nitrogen from the soil, rather than converting it to ammonia, making this option also incorrect.

- **Nitrogen Fixation**: This is the process where atmospheric nitrogen (N₂) is converted into ammonia (NH₃) or related compounds by certain microbes. This is the correct answer to the question as it directly involves the conversion of nitrogen to ammonia.

- **Haber’s Process**: This is an industrial method for synthesizing ammonia from nitrogen and hydrogen gases, but it is not a microbial process. Therefore, this option is also incorrect.

3. **Conclusion**: The process of conversion of nitrogen to ammonia by microbes is known as **Nitrogen Fixation**.

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