To answer this question, we need to understand the concept of pollution and its historical development.
Option A) In the Rigvedic period - This option is incorrect because the Rigvedic period refers to the ancient period in India, around 1500-1200 BCE, and there is limited evidence or mention of pollution during this time.
Option B) In the post-Vedic period - This option is correct because the concept of pollution started to emerge clearly during the post-Vedic period, which is considered to be around 600 BCE and onwards. This period saw the development of various texts and treatises that discussed pollution and its implications in society.
Option C) In the post-Gupta age - This option is incorrect because the post-Gupta age refers to a period in Indian history from the 6th to the 12th century CE. While this period witnessed advancements in various fields, the concept of pollution was already established during the earlier post-Vedic period.
Option D) In the age of Dharma Shastras - This option is incorrect because the Dharma Shastras, which are ancient texts that provide guidelines on ethical and moral conduct, were written during the post-Vedic period. They addressed various aspects of life but did not specifically focus on pollution.
Therefore, the correct answer is B) In the post-Vedic period. This option is correct because it was during this period that the concept of pollution started to emerge clearly and became a subject of discussion in various texts and treatises.