Assertion: The social background of the Mauryas, who ruled over a large empire, has been hotly debated.
Reason: While later Buddhist texts suggested they were Kshatriyas, Brahmanical texts described them as being of low origin.

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

The Shastras dictated that only Kshatriyas were eligible to assume the role of kings. Nevertheless, the origins of several prominent ruling lineages likely diverged from this traditional norm. For instance, the Mauryas, who held sway over a vast empire, have been the subject of intense debate concerning their social background. According to certain Buddhist texts, they were regarded as Kshatriyas, while Brahmanical texts portrayed them as being of "low" origin. The Shungas and Kanvas, who succeeded the Mauryas, were Brahmanas, further exemplifying the complex and varied social backgrounds of ruling dynasties in ancient India.