The correct answer is A. Ashoka.
Ashoka was an Indian ruler who was converted to Buddhism. He was an emperor in India on the side of Maurya Dynasty whereby he ruled Indian subcontinent for long.
He waged a war against Kalinga state where he conquered and converted to Buddhism. He witnessed the war which he waged so as to conquer it, whereby it resulted to many people being deported and others died.
H ewent back to edicts and the Ashoka pillars where he send Buddhist monks to central Asia and Sri Lanka.
The purpose for the Buddhist was to establish monuments which marked the important sites for the life of Gautama Buddha.