Assertion : Curdling is required in the manufacture of cheese.
Reason : Lactic acid bacteria are used for the purpose.

Options

A. if both are true with reason being correct explanation
B. both are true but reason is not correct explanation
C. assertion is true but reason is wrong
D. both are wrong

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that curdling is required in the manufacture of cheese. This is true because cheese production involves the transformation of milk into curd through the process of curdling.

2. **Understanding the Process of Curdling:**
- Curdling is the process where milk, which is an emulsion of fat and water, is converted into a semi-solid mass known as curd. This is essential for cheese production as curd is the primary ingredient.

3. **Identifying the Role of Lactic Acid Bacteria:**
- The reason provided states that lactic acid bacteria are used for the purpose of curdling. This is also true because lactic acid bacteria ferment lactose (the sugar in milk) into lactic acid, which helps in coagulating the milk proteins (casein) and forming curd.

4. **Connecting Assertion and Reason:**
- Both the assertion and reason are true. Curdling is indeed necessary for cheese production, and lactic acid bacteria play a significant role in this process by facilitating the curdling through lactic acid production.

5. **Evaluating the Explanation:**
- While both statements are true, the reason does not fully explain the assertion. Curdling can also be achieved through other methods, such as using enzymes, not just lactic acid bacteria. Therefore, the reason is true, but it is not the only method for curdling.

6. **Conclusion:**
- Both the assertion and reason are true, but the reason is not the correct explanation of the assertion since there are alternative methods to achieve curdling.

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