Option c is the correct answer. The earliest deciphered epigraphic inscriptions are the Edicts of Ashoka, dating back to the 3rd century BCE. These edicts are written in the Prakrit language using the Brahmi script. They offer invaluable historical insights into Ashoka's reign and his propagation of Buddhist principles. Prakrit was a more accessible language compared to Sanskrit, which was used for more formal and scholarly purposes. The use of Prakrit in inscriptions allowed rulers and authorities to communicate with a wider audience and convey important messages to their subjects.