The correct answer is D. To equal that of Brahman.
Explanation
In Hinduism, the atman is a concept to refer to the essence of the individual. This in turn is related to Brahman (the essential unit of everything that exists in the universe). So, the relationship between atman and Brahman is that Brahman, being the essential unit of everything existing in the universe, encompasses the essence of being, that is, atman in a singular sense. Moreover, the atman or indivudual should work to become or to equal the Brahman. So the correct answer is D. To equal that of Brahman.