Question

Assertion (A) : Besides curdling of milk, LAB also improves its nutritional quality by increasing Vitamin B₁₂.

Reason (R) : LAB, when present in the stomach checks disease-causing microbes.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

Both statements are true, but the stomach role of LAB does not explain the rise in vitamin B12.

Answer 1

The Correct Option is B

Step 1: Check the assertion:
Lactic acid bacteria (LAB) such as Lactobacillus turn milk into curd. NCERT says LAB also improve the nutritional quality of milk by increasing vitamin B12.
So the assertion is true.

Step 2: Check the reason:
NCERT also says that LAB in our stomach (gut) play a useful role in checking disease-causing microbes.
So the reason is also true.

Step 3: Does the reason explain the assertion?:
Increasing vitamin B12 in curd is a change in the milk outside the body. Checking disease microbes in the stomach is a separate benefit.
The reason does not explain why vitamin B12 increases.

Step 4: Pick the option:
Both are true, but R is not the explanation of A. That is option (B). Option (A) is wrong because of the missing link, (C) and (D) are wrong because no statement is false.

Final Answer:
Both statements are true, but the reason does not explain the assertion, option (B).