Correct Answer - Option (C) Vithi
Explanation: The fourth layer of administration was at group or villages (Vithi) or town level. For each village there was a village assembly consisting of village elders, guided by a village headman. This Gram sabha was smallest administration unit. The head of the village was called Gramapati or Gramadhyaksha. Kutumbis and Mahattaras are other words used for similar village level officers.