The correct answer is: d) All of the above.
Mizo communities faced a number of challenges during this period, including inter-tribal conflicts over resources, incursions by larger neighboring kingdoms, and environmental factors like droughts or floods.
Inter-tribal conflicts were common in the Mizo Hills, as different tribes competed for land, water, and other resources. These conflicts could be violent, and often resulted in deaths and injuries.
Incursions by larger neighboring kingdoms were also a major challenge for Mizo communities. These kingdoms would often raid Mizo villages, taking people as slaves or livestock. They would also sometimes try to conquer the Mizo Hills, which would lead to further conflict.
Environmental factors like droughts or floods could also have a devastating impact on Mizo communities. Droughts could lead to crop failures, which would make it difficult for people to get food. Floods could destroy homes and crops, and could also lead to deaths and injuries.
All of these challenges made life difficult for Mizo communities during this period. However, they were also a source of strength, as they forced the Mizo people to develop strong social bonds and a resilience that has helped them to survive and thrive in the face of adversity.