Step-by-step explanation:
Primary Source. The evidence that gives this away is that it is a fragment of a stone dated back to 232 B.C.
The author of this artifact was Asoka. The Mauryan Leader.
The purpose of creating this artifact was to assert Asoka's Buddhism and support his desire to spread dharma.
Evidence that makes me think this is that the tenets have Buddhism engraved them meaning that they had some sort of meaning to the leader.
Something that we have today that is similar to Asoka's rock pillars are edicts?
I hope this helps you out. I wasn't too sure about the last question though.