A major river flowing through the northern part of Mizoram is the:

The correct answer is: a) Kolodyne (Chhimtuipui).

The Kolodyne (Chhimtuipui) is a river in Mizoram, India. It is the longest river in the state, flowing for about 200 kilometers (120 mi). The river originates in the hills of the Mizo Hills and flows northward through the state, eventually joining the Barak River in Assam. The Kolodyne is a major source of water for irrigation and drinking water in Mizoram. It is also a popular destination for fishing and boating.

The other options are incorrect for the following reasons:

• Option b, Barak, is a river in Assam and Bangladesh. It is the longest river in the Barak Valley and the second longest river in Assam. The Barak originates in the Manipur Hills and flows eastward through the Barak Valley, eventually joining the Brahmaputra River in Bangladesh.
• Option c, Subansiri, is a river in Arunachal Pradesh and Assam. It is the longest river in Arunachal Pradesh and the third longest river in Assam. The Subansiri originates in the Himalayas and flows eastward through Arunachal Pradesh, eventually joining the Brahmaputra River in Assam.
• Option d, Teesta, is a river in Sikkim, West Bengal, and Bangladesh. It is the longest river in Sikkim and the fourth longest river in West Bengal. The Teesta originates in the Himalayas and flows eastward through Sikkim, West Bengal, and Bangladesh, eventually joining the Brahmaputra River in Bangladesh.