Assertion : Curd is more nutritious than milk .
Reason : LAB present in curd checks the growth of disease- causing microbes.

Options

A. If both Assertion and Reason are true and the reason is the correct explanation of the assertion , then mark (1) .
B. If both Assertion and Reason are true but the reason is not the correct explanation of the assertion , then mark (2).
C. If assertion is true but Reason is false , then false , then mark(3).
D. If both assertion is true Reason are false , then Mark (4).

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Curd is more nutritious than milk." To evaluate this, we need to consider the nutritional components of curd compared to milk.

2. **Analyzing the Nutritional Content**: Curd is made from milk through the action of lactic acid bacteria (LAB), primarily Lactobacillus. During this process, lactose (milk sugar) is converted into lactic acid, which not only thickens the milk but also enhances its nutritional profile. Curd contains additional beneficial components such as organic acids and vitamins, particularly Vitamin B12, which are not present in significant amounts in milk.

3. **Understanding the Reason**: The reason provided states that "LAB present in curd checks the growth of disease-causing microbes." This is true, as LAB can inhibit harmful bacteria in the digestive system, contributing to gut health.

4. **Evaluating the Relationship**: While both the assertion and reason are true, the reason does not directly explain why curd is more nutritious than milk. The nutritional superiority of curd is primarily due to the presence of organic acids and vitamins, rather than the presence of LAB alone.

5. **Conclusion**: Therefore, both statements are correct, but the reason does not correctly explain the assertion. The correct answer is that both the assertion and reason are true, but the reason is not a valid explanation for the assertion.

### Final Answer:
Both the assertion and reason are true, but the reason does not correctly explain the assertion.

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