Option 1 suggests that the Nyishi tribe is mainly found in Andaman and Nicobar islands. However, this is incorrect, as the islands are home to different tribes like the Great Andamanese, Onge, Jarwa, among others, not the Nyishi tribe.

Option 2 is the correct answer. The Nyishi tribe is primarily found in Arunachal Pradesh, in north-eastern India. They are the largest ethnic group in the state and have a rich culture and tradition unique to their community.

Option 3 mentions Nilgiri-Kerala, which is incorrect as the Nyishi tribe is not native to that location. Kerala is known for other tribes such as Kurichiyar, Kurumbar, and Paniyar apart from many others.

Option 4 refers to the Kashmir Valley which is incorrect. The tribes in this region include Gujjars, Bakarwals, and Pahadis, and the Nyishi tribe is not found in this area.

Therefore, the Nyishi tribe is predominantly located in Arunachal Pradesh, India.