In the given question, a statement of Assertion is followed by a statement of Reason. Mark the correct answer.

Assertion: The conception of social pollution, intrinsic to the caste system, was according to Al Bruni, contrary to the laws of nature.
Reasoning: Al Biruni believed that that everything which falls into a state of impurity strives and succeeds in regaining its original condition of purity. The sun cleanses the air, and the salt in the sea prevents the water from becoming polluted. It were not so, life on earth would have been impossible.

Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

In spite of his acceptance of the Brahmanical description of the caste system, Al-Biruni disapproved of the notion of pollution. He remarked that everything which falls into a state of impurity strives and succeeds in regaining its original condition of purity. The sun cleanses the air, and the salt in the sea prevents the water from becoming polluted