Assertion(A): The Government of India Act, 1919 was passed by the British Parliament to introduce 'Diarchy' in the provincial government. Reason (R) : Montague-Chelmsford Reforms Committee had recommended the introduction of 'Diarchy' in the provincial government.

The Government of India Act, 1919, was enacted by the British Parliament to implement the policy of 'progressive realization of responsible government' in India [5]. A central feature of this Act was the introduction of 'Diarchy' (dual government) in the provincial administration, which divided subjects into 'transferred' and 'reserved' categories [5]. This legislative action was directly based on the recommendations of the Montagu-Chelmsford Report (1918), prepared by Secretary of State Edwin Montagu and Viceroy Lord Chelmsford [4]. The report served as the theoretical basis and scheme for the constitutional changes embodied in the 1919 Act [5][t1]. Therefore, both the assertion regarding the introduction of Diarchy and the reason citing the committee's recommendations are true, with the latter providing the correct explanation for the enactment of the former.

Sources

1. [2] Indian Polity, M. Laxmikanth(7th ed.) > Chapter 1: Historical Background > Government of India Act of 1919 > p. 6
2. [5] https://en.wikipedia.org/wiki/Montagu%E2%80%93Chelmsford_Reforms
3. [1] Introduction to the Constitution of India, D. D. Basu (26th ed.). > Chapter 1: THE HISTORICAL BACKGROUND > Utility of a Historical Retrospect. > p. 4
4. [4] History , class XII (Tamilnadu state board 2024 ed.) > Chapter 4: Advent of Gandhi and Mass Mobilisation > 4.2 Montagu–Chelmsford Reforms > p. 44