How far south did Asoka extend the Mauryan Empire?

The empire was the largest political entity that has existed in the Indian subcontinent, extending over 5 million square kilometres (1.9 million square miles) at its zenith under Ashoka.

answer; i believe that the correct answer is ( troxel v. granville);

i heard they are taking it off i hope this isn't true but otherwise if it doesn't get taken off it will probably be in early december or early january of 2018-2019