The study of feudatory states and power structures in Arunachal Pradesh helps understand:

The correct answer is: d) All of the above.

The study of feudatory states and power structures in Arunachal Pradesh helps understand historical social organization, colonial influence, and the evolution of governance systems.

• Historical social organization: The study of feudatory states and power structures can help us understand how people in Arunachal Pradesh have organized themselves socially over time. This includes understanding the different groups that have existed in the region, their relationships with each other, and how they have changed over time.
• Colonial influence: The study of feudatory states and power structures can also help us understand the impact of colonialism on Arunachal Pradesh. This includes understanding how the British and other colonial powers interacted with the people of the region, and how this interaction shaped the development of feudatory states and power structures.
• The evolution of governance systems: The study of feudatory states and power structures can also help us understand the evolution of governance systems in Arunachal Pradesh. This includes understanding how different forms of government have emerged and developed over time, and how they have responded to the challenges of the modern world.

In conclusion, the study of feudatory states and power structures in Arunachal Pradesh can help us understand a wide range of issues related to the history, culture, and politics of the region.