The correct answer is: a) Direct rule.
The British administration of the Naga Hills was characterized by a policy of direct rule. This meant that the British government exercised complete control over the region, with little or no input from local leaders. The British appointed their own officials to administer the Naga Hills, and they imposed their own laws and customs on the region. This policy of direct rule led to a great deal of resentment among the Naga people, who felt that they were being treated as second-class citizens.
Option b) is incorrect because the British did not allow local chiefs to have any real power. They were appointed by the British government and were responsible for carrying out British policies.
Option c) is incorrect because the Naga Hills were never granted complete autonomy. The British government always retained ultimate control over the region.
Option d) is incorrect because the Naga Hills were never integrated into the princely states. The British government administered the Naga Hills directly, rather than through the princely states.