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

Assertion (A):Carbon monoxide is a serious asphyxiant; even a short exposure may have fatal health effects.

Reason (R):Haemoglobin present in the blood has a greater affinity towards carbon monoxide than oxygen.

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

Both statements are true and the reason correctly explains the assertion about carbon monoxide's danger.

The assertion is sound: carbon monoxide is a serious asphyxiant whose brief exposure can be fatal.

The reason is sound: haemoglobin binds carbon monoxide far more readily than it binds oxygen.

Because haemoglobin locks onto carbon monoxide, less oxygen reaches the tissues, which is exactly why the gas asphyxiates.

The resulting carboxyhaemoglobin cannot carry oxygen around the body.

Colourless and odourless, carbon monoxide gives no warning of its presence.

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