Tista, Manas, Subansiri are tributaries of

1Lepchas have been accorded the Primitive Tribe Group status by the Government of Sikkim. The primary aim, among others, is to provide protection. But the way things are planned for Dzongu is unjust. It is a plan to uproot the last bastion of the Lepchas./

2Image result for Manas is what tribe

In the 19th century versions, Manas is the leader of the Nogay people, while in versions dating after 1920, Manas is a Kyrgyz and a leader of the Kyrgyz.

3Image result for Manas is what tribe

In the 19th century versions, Manas is the leader of the Nogay people, while in versions dating after 1920, Manas is a Kyrgyz and a leader of the Kyrgyz.

Explanation:

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answer; the nazca plate is converging with the south american plate