Explanation:

- Option 1: Sone

- The North Koel River is a tributary of the Sone River.

- It originates in the Chota Nagpur Plateau in Jharkhand, India, and flows through Jharkhand and Bihar before converging with the Sone River.

- The Sone River is itself a major tributary of the Ganges River.

- Correct Answer: Sone

- Option 2: Cauvery

- The Cauvery River flows through the Indian states of Karnataka and Tamil Nadu.

- It is primarily associated with southern India and is not geographically connected to the North Koel River.

- Option 3: Godavari

- The Godavari River is one of the major rivers in central and southern India, flowing through Maharashtra, Telangana, and Andhra Pradesh.

- It does not have any direct connection with the North Koel River.

- Option 4: Yamuna

- The Yamuna River flows through northern India, primarily through the states of Uttarakhand, Haryana, Delhi, and Uttar Pradesh.

- The North Koel River does not contribute to the Yamuna River system.