History · British Expansion & Battle of Buxar

With reference to the political consequences of the Battle of Buxar (1764), consider the following statements: I. The Treaty of Allahabad (1765) was entered into between Robert Clive and the Mughal Emperor Shah Alam II. II. By this treaty, the East India Company obtained the Diwani rights of Bengal, Bihar, and Orissa. III. In the system of Dual Government introduced thereafter, the East India Company exercised Nizamat powers, while the Nawab of Bengal retained Diwani authority. IV. The Battle of Buxar was fought between the East India Company under Hector Munro and the combined forces of Mir Qasim, Shuja-ud-Daula, and Shah Alam II. How many of the statements given above are correct?