The correct option is B Assam, Meghalaya, Tripura and Mizoram
The sixth Schedule deals with the administration of Tribal Areas in the states of Assam, Meghalaya, Tripura, Mizoram. It provides for the constitution of District Councils and Regional Councils. Governors of these four states are empowered to declare some tribal dominated districts/areas of these states as autonomous districts and autonomous regions by order.