A major river that originates in Nagaland is the:

Dhansiri
Brahmaputra
Barak
Tista

The correct answer is: a) Dhansiri.

The Dhansiri is a river in India that originates in the Naga Hills and flows through the states of Nagaland, Assam, and Manipur. It is a tributary of the Brahmaputra River. The Dhansiri is about 250 kilometers long and has a drainage basin of about 10,000 square kilometers. The river is used for irrigation, drinking water, and hydroelectric power generation.

The Brahmaputra is the largest river in India and the third largest river in Asia. It originates in the Himalayas and flows through the states of Arunachal Pradesh, Assam, and Bangladesh. The Brahmaputra is about 2,900 kilometers long and has a drainage basin of about 930,000 square kilometers. The river is used for irrigation, drinking water, and hydroelectric power generation.

The Barak is a river in India that originates in the Manipur Hills and flows through the states of Manipur, Assam, and Tripura. It is a tributary of the Meghna River. The Barak is about 370 kilometers long and has a drainage basin of about 20,000 square kilometers. The river is used for irrigation, drinking water, and hydroelectric power generation.

The Tista is a river in India that originates in the Himalayas and flows through the states of Sikkim, West Bengal, and Bangladesh. It is a tributary of the Brahmaputra River. The Tista is about 315 kilometers long and has a drainage basin of about 18,000 square kilometers. The river is used for irrigation, drinking water, and hydroelectric power generation.