The correct answer is c) Tribal chieftains.
Bhuyans were a group of tribal chieftains who ruled over the Brahmaputra valley in Assam, India, from the 12th to the 17th centuries. They were originally a branch of the Bodo people, but they developed their own distinct culture and identity. The Bhuyans were known for their military prowess and their resistance to outside rule. They were eventually defeated by the Mughal Empire in the 17th century, but their legacy continues to this day.
Option a) British colonial officials is incorrect because the Bhuyans were not British colonial officials. They were a group of tribal chieftains who ruled over the Brahmaputra valley in Assam, India, from the 12th to the 17th centuries.
Option b) Missionaries is incorrect because the Bhuyans were not missionaries. They were a group of tribal chieftains who ruled over the Brahmaputra valley in Assam, India, from the 12th to the 17th centuries.
Option d) Ancient kings is incorrect because the Bhuyans were not ancient kings. They were a group of tribal chieftains who ruled over the Brahmaputra valley in Assam, India, from the 12th to the 17th centuries.