The correct option is Dhamma Mahamatta.
Explanation
Ashoka introduced a unique administrative innovation to propagate his policy of moral and ethical conduct known as Dhamma. He appointed a special class of high-ranking officials specifically dedicated to the welfare of the people and the dissemination of Dhamma principles across his empire and in neighboring regions.
Analysis of Options:
- Rajukas Rajukas: These were provincial officials primarily responsible for land measurement and revenue administration. Later, Ashoka granted them judicial powers to punish and reward people, as mentioned in Pillar Edict IV. While they assisted in administration, their primary role was not the propagation of Dhamma.
- Dhamma Mahamatta Dhamma Mahamatta: Correct. Ashoka instituted the office of Dhamma Mahamattas in the 14th year of his reign (mentioned in Major Rock Edict V). Their specific duties included spreading the message of Dhamma, ensuring the welfare of prisoners, and looking after the interests of various religious sects (Sangha, Brahmans, Ajivikas, etc.).
- Pativedakas Pativedakas: These were special reporters or spies mentioned in Major Rock Edict VI. Their duty was to report the affairs of the people to the king at any time, ensuring the king remained accessible to his subjects.
- Agrahara Agrahara: This term refers to land grants given to Brahmins, which were typically tax-free. It is a land tenure system prevalent in ancient India (becoming prominent in the Gupta period) and is not the title of a Mauryan officer.
Key Takeaway: The Dhamma Mahamattas were a specialized cadre of officials created by Ashoka specifically to enforce and propagate the moral code of Dhamma and ensure the welfare of all religious sects.