Explanation:

- The Mahanadi river is a major river in India that flows through various states before emptying into the Bay of Bengal.

- Option 1, Chhattisgarh: The Mahanadi basin extensively covers the state of Chhattisgarh. It is one of the primary areas through which the river flows.

- Option 2, Uttar Pradesh: The Mahanadi basin does not extend into the state of Uttar Pradesh. This state lies north of the typical course of the river.

- Option 3, Jharkhand: The basin slightly covers Jharkhand, but it is not a major area of flow.

- Option 4, Odisha: Odisha is another primary state covered extensively by the Mahanadi basin.

Option 2, Uttar Pradesh: is the correct answer.

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