What is NOT true about the caste system in ancient India?

The correct answer is option 4- None of the above.

Caste refers to a set of hierarchically ordered social categories. The ideal order was laid down in the Dharmasutras and Dharmashastras. 

Brahmanas claimed that  this order, in which they were ranked first, was divinely ordained, while placing groups classified as Shudras and “untouchables” at the very bottom of the social order.

Positions within the order were supposedly determined by birth.