Concept:Kunwar Singh was a prominent leader of the 1857 revolt who led the uprising in Bihar.
Explanation:Kunwar Singh, also known as Babu Kunwar Singh, was from the Ujjainiya clan of Parmar Rajputs.
His home was in Jagdispur, which is in the Bhojpur district of Bihar.
At the age of 80, he led armed soldiers against the British East India Company.
He was the chief organizer of the revolt in Bihar, making Bihar the correct region.
Other leaders are linked to different places: Lucknow (Begum Hazrat Mahal), Jhansi (Rani Lakshmi Bai), Kanpur (Nana Sahib), Delhi (Bahadur Shah Zafar).
Thus, the revolt in Bihar was spearheaded by Kunwar Singh.
Answer:C. Bihar