Kunwar Singh was the King of

Hamirpur
Dheerpur
Jagdishpur
Rampur

The correct answer is C. Jagdishpur.

Kunwar Singh was a freedom fighter who fought against the British East India Company in the Indian Rebellion of 1857. He was the Raja of Jagdishpur, a small kingdom in the state of Bihar. He was born in 1777 and died in 1858.

Hamirpur is a city in the state of Uttar Pradesh. Dheerpur is a village in the state of Uttar Pradesh. Rampur is a city in the state of Uttar Pradesh.

Hamirpur, Dheerpur, and Rampur are all located in the state of Uttar Pradesh. However, Jagdishpur is located in the state of Bihar. Therefore, Kunwar Singh was the Raja of Jagdishpur.