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

Assertion: Al Biruni, in his account, attempted his acceptance of the Brahmanical description of the caste system.
Reasoning: The conception of social pollution, intrinsic to the caste system, was according to him, contrary to the laws of nature.

Both the Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.

The correct answer is Opiion 2: Both the Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.

Assertion: Al Biruni, in his account, attempted his acceptance of the Brahmanical description of the caste system. This is correct.
Reasoning: The conception of social pollution, intrinsic to the caste system, was according to him, contrary to the laws of nature. This is also correct.

The reason does not explain A i.e. as to why Al Biruni, in his account, attempted his acceptance of the Brahmanical description of the caste system

"Al-Biruni tried to explain the caste system in India by looking for parallels in other societies. He noted that in ancient Persia, four social categories were recognised: those of knights and princes; monks, fire-priests and lawyers; physicians, astronomers and other scientists; and finally, peasants and artisans. In other words, he attempted to suggest that social divisions were not unique to India. At the same time he pointed out that within Islam all men were considered equal, differing only in their observance of piety. 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. If it were not so, insisted Al-Biruni, life on earth would have been impossible. The conception of social pollution, intrinsic to the caste system, was according to him, contrary to the laws of nature."