Under which among the following treaties, the British East India Company secured the Diwani right of Bengal, Bihar and Orissa ?
[A] Alinagar
[B] Faizabad
[C] Allahabad
[D] Benaras

Treaty of Allahabad ( 16 August 1765), it was the outcome of the Battle of Buxar (1764). Robert Clive (Governor General of Bengal) made a separate treaty with Mughal Emperor Shah Alam II and Nawab of Awadh Shuja-ud-daullah. A/c to this treaty, Mughal Emperor granted Fiscal Rights (Diwani) to the East India Company at Bengal, Bihar and Orissa.