Nitrifying bacteria convert :

Options

A. Nitrates into nitrites
B. Nitrites into nitrates
C. Ammonium salts into nitrates
D. Ammonium salts into amino acid

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrifying Bacteria**: Nitrifying bacteria are a group of bacteria that play a crucial role in the nitrogen cycle by converting ammonia into nitrates through a two-step process.

2. **First Step - Ammonia to Nitrites**: The first step in nitrification involves the oxidation of ammonia (NH₃) into nitrites (NO₂⁻). This process is primarily carried out by bacteria such as Nitrosomonas.

3. **Second Step - Nitrites to Nitrates**: The second step involves the further oxidation of nitrites (NO₂⁻) into nitrates (NO₃⁻). This step is typically performed by bacteria such as Nitrobacter.

4. **Summary of the Process**: Therefore, nitrifying bacteria convert ammonia into nitrites and then nitrites into nitrates.

5. **Conclusion**: The correct answer to the question "Nitrifying bacteria convert:" is that they convert ammonium salts into nitrates.

**Final Answer**: Nitrifying bacteria convert ammonium salts into nitrates.

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