The correct answer is Lord Cornwallis.
The system of “Dual Government” was introduced in Bengal (including Bihar) by Lord Cornwallis in 1793. Under this system, the British East India Company took over the administration of revenue and justice in Bengal, while the Nawab of Bengal retained control over his personal estates and some other areas.
Robert Clive was the first British Governor of Bengal. He was responsible for the Battle of Plassey in 1757, which marked the beginning of British rule in India.
Warren Hastings was the second British Governor of Bengal. He was responsible for the introduction of the Permanent Settlement in Bengal in 1793.
Lord Dalhousie was the third British Governor-General of India. He was responsible for the Doctrine of Lapse, which led to the annexation of several Indian states.
The system of “Dual Government” was not without its problems. The British East India Company was not always efficient in its administration of revenue and justice. The Nawab of Bengal was also not always happy with the way the British were running his country.
However, the system of “Dual Government” did provide a measure of stability in Bengal. It also allowed the British to learn more about the Indian way of life and to develop a better understanding of Indian culture.