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Assertion : In crustose lichen stage , ...

Assertion : In crustose lichen stage , by corroding action , soil formation occurs but this action is very slow.
Reason : Crustose lichens produce carbonic acid which corrodes the rock.

A

If both Assertion and Reason are true and Reason is correct explanation of Assertion.

B

If both Assertion and Reason is not correct explanation of Assertion.

C

If Assertion is true but Reason is false.

D

If both Assertion and Reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question, we will analyze both statements step by step. ### Step 1: Understand the Assertion The assertion states that in the crustose lichen stage, soil formation occurs due to the corroding action of the lichens, but this process is very slow. - **Explanation**: Crustose lichens are among the first organisms to colonize bare rock surfaces. They contribute to soil formation by breaking down the rock material over time. However, this process is gradual and takes a significant amount of time. ### Step 2: Understand the Reason The reason states that crustose lichens produce carbonic acid, which corrodes the rock. - **Explanation**: Crustose lichens secrete substances, including carbonic acid, which helps in the weathering of rocks. This chemical reaction contributes to the breakdown of the rock, facilitating soil formation. ### Step 3: Analyze the Relationship Now, we need to determine if the reason provided correctly explains the assertion. - The assertion is true because crustose lichens do contribute to soil formation, albeit slowly. - The reason is also true because the production of carbonic acid by lichens does lead to the corrosion of rocks. ### Step 4: Conclusion Since both the assertion and reason are true, and the reason correctly explains the assertion, we can conclude that the correct option is: **Both assertion and reason are true, and the reason is the correct explanation of the assertion.** ### Final Answer Both assertion and reason are true, and the reason is the correct explanation of the assertion. ---
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