Explanation:

- Barak River:

- It's not a desert river.

- Flows through northeastern India.

- Part of the Barak Valley ecosystem.

- Rupen River:

- A small river in Gujarat, India.

- Flows through semi-arid regions.

- Influenced by desert conditions.

- Banas River:

- Located in Rajasthan.

- Passes through arid and semi-arid regions.

- Machchhu River:

- Found in Gujarat, India.

- Traverses dry land, influenced by desert.

Correct Answer: Barak