Which of the following is/are tributary/tributaries of Brahmaputra?

1. Dibang

2. Kameng

3. Lohit

Select the correct answer using the code given below:

The correct answer is 1, 2 and 3 — that is, Dibang, Kameng, and Lohit are all tributaries of the Brahmaputra river.

Let us understand the Brahmaputra river system and then examine each of the three rivers one by one to confirm why all of them qualify as tributaries.

Overview of the Brahmaputra River System
The Brahmaputra is one of the major trans-boundary rivers of Asia. It originates from the Chemayungdung glacier near Lake Mansarovar in Tibet (where it is known as the Tsangpo). It flows eastward across Tibet, then makes a dramatic U-turn (called the Great Bend) near the Namcha Barwa peak, cuts through the Himalayas, and enters India through Arunachal Pradesh. In India, it flows westward through Assam and eventually merges with the Ganga–Padma system in Bangladesh. Along this journey, it collects numerous tributaries — mostly from its left (northern) and right (southern) banks.

Statement 1 — Dibang: A Tributary of Brahmaputra ✔
The Dibang (also called Sikang) is a significant left-bank tributary of the Brahmaputra. It originates in the mountainous terrain of the Dibang Valley district of Arunachal Pradesh in the eastern Himalayas. After flowing southward through the Mishmi Hills, it joins the Brahmaputra (Lohit river confluence area) near Sadiya in Assam. The Dibang is part of the three-river confluence at Sadiya (along with Lohit and Brahmaputra itself), which forms the characteristic wide, braided channel of the Brahmaputra in upper Assam. So, Statement 1 is correct.

Statement 2 — Kameng: A Tributary of Brahmaputra ✔
The Kameng (known as the Jia Bhoreli in its lower course in Assam) is a right-bank tributary of the Brahmaputra. It originates from the glaciers of Tawang district in western Arunachal Pradesh. It flows southward through the Kameng district of Arunachal Pradesh, passes through the foothills, and eventually meets the Brahmaputra near Tezpur in Assam. The Kameng river is closely associated with the Pakke Tiger Reserve and the Nameri National Park in the region. So, Statement 2 is correct.

Statement 3 — Lohit: A Tributary of Brahmaputra ✔
The Lohit is another major left-bank tributary of the Brahmaputra. It originates in the Zayul region of Tibet (China) and enters India through Arunachal Pradesh via the Lohit district. It flows southwestward and merges with the Dibang and the Brahmaputra near Sadiya in Assam. In fact, the combined confluence of the Lohit, Dibang, and Brahmaputra is so prominent that many geographers consider this junction as the point where the Brahmaputra truly begins its broad plains course in India. The town of Sadiya sits at this confluence. So, Statement 3 is correct.

Summary Table

Since all three rivers — Dibang, Kameng, and Lohit — are established tributaries of the Brahmaputra, the correct answer is unambiguously "1, 2 and 3".