The correct option is 1 and 3 only
Explanation
The Brahmaputra river system is one of the largest in the world, traversing through Tibet (China), India, and Bangladesh.
Statement 1 is Correct
The Brahmaputra originates in the Chemayungdung glacier of the Kailash range near the Mansarovar lake. It flows eastward longitudinally for a considerable distance in southern Tibet.
Statement 2 is Incorrect
In Tibet, the river is known as the Tsangpo, which means 'the purifier'. It is known as the Dihang (or Siang) only after it enters India through Arunachal Pradesh. Upon entering the Assam valley, it is joined by two major tributaries, the Dibang and the Lohit, and is thereafter known as the Brahmaputra.
Statement 3 is Correct
The Rango Tsangpo is a major right-bank tributary of the Brahmaputra (Tsangpo) in Tibet. It joins the main river near Lhatse Dzong.
Key Takeaway:
The Brahmaputra is known by different names along its course: Tsangpo in Tibet, Dihang/Siang in Arunachal Pradesh, Brahmaputra in Assam, and Jamuna in Bangladesh.