Bacteria responsible for fermentation of diary milk are

Options

A. Lactobacillus
B. Hay Bacillus
C. Acetobacter
D. Rhizobium.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the specific type of bacteria responsible for the fermentation of dairy milk.

2. **Understand Fermentation**: Fermentation is a metabolic process that converts sugars (like lactose in milk) into acids, gases, or alcohol. In the case of dairy milk, the primary product is lactic acid.

3. **Know the Options**: The options provided are:
- A) Lactobacillus
- B) Haebacillus
- C) Acetobacter
- D) Rhizobium

4. **Analyze Each Option**:
- **Lactobacillus**: This genus of bacteria is known for its role in the fermentation of milk. It converts lactose into lactic acid, which increases the acidity of the milk and causes it to thicken.
- **Haebacillus**: This is not a well-known genus related to dairy fermentation.
- **Acetobacter**: This bacterium is primarily involved in the production of vinegar, not dairy fermentation.
- **Rhizobium**: This genus is known for its role in nitrogen fixation in plants, not in dairy fermentation.

5. **Conclude the Correct Answer**: Based on the analysis, the bacteria responsible for the fermentation of dairy milk is **Lactobacillus**.

6. **Final Answer**: The correct answer is **A) Lactobacillus**.

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