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

Assertion (A):Ocean acidification and the negative impact on corals, algae and shellfish are caused by excess carbon dioxide in sea water.

Reason (R):The natural carbon sinks have a maximum limit of carbon dioxide absorption.

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 the assertion and the reason are true, and the reason explains the assertion.

The assertion states that excess carbon dioxide in sea water acidifies the ocean and harms corals, algae and shellfish.

The reason notes that natural carbon sinks can absorb only up to a maximum limit of carbon dioxide.

Once absorption piles up, the added carbon dioxide dissolves into carbonic acid and lowers the water's pH.

The reason therefore accounts for why the ocean keeps taking in carbon dioxide until acidification sets in.

More acidic water dissolves the calcium carbonate that shells and coral skeletons are built from.

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