Given below are two statements, an Assertion (A) and a Reason (R). Choose the correct answer.

Assertion (A):Methaemoglobinaemia is a condition in which blood is not able to carry and deliver enough oxygen to the body.

Reason (R):Consuming drinking water with a high nitrate level may cause methaemoglobinaemia.

ABoth (A) and (R) are true and (R) is the correct explanation of (A) ✓ Correct

BBoth (A) and (R) are true but (R) is not the correct explanation of (A)

C(A) is true, but (R) is false

D(A) is false, but (R) is true

Correct answer: (A) Both (A) and (R) are true and (R) is the correct explanation of (A)

Explanation

Methaemoglobinaemia is a condition in which blood cannot carry and deliver enough oxygen, making the assertion true.

High nitrate in drinking water can indeed cause methaemoglobinaemia, making the reason true.

Nitrate converts normal haemoglobin into methaemoglobin, which cannot bind oxygen properly.

This mechanism shows the reason directly explains why the assertion happens.

The reason therefore correctly accounts for the assertion.

This is the basis of blue baby syndrome affecting bottle-fed infants.

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