Assertion (A) : Partition of Bengal in 1905 brought to an end the Moderates’ role in the Indian freedom movement. Reason (R) : The Surat session of Indian National Congress separated the Extremists from the Moderates.

Assertion is false and Reason is true. The partition of Bengal provoked the Swadeshi and Boycott movements and encouraged extremist activism, but it did not immediately end the Moderates’ role—Moderates led early anti‑partition efforts and continued to dominate Congress politics at the 1905 session while debating the limits of Swadeshi tactics [2]. The formal rupture between Extremists and Moderates occurred at the Surat session of 1907, where irreconcilable positions over presidency and policy produced the well‑known Surat Split, separating the two wings of the Congress [3]. Thus R correctly states the cause of formal separation, but A overstates the immediate effect of the 1905 partition on Moderate influence.

Sources

1. [1] Rajiv Ahir. A Brief History of Modern India (2019 ed.). SPECTRUM. > Chapter 12: Era of Militant Nationalism (1905-1909) > The Swadeshi and Boycott Movement > p. 280
2. [2] Rajiv Ahir. A Brief History of Modern India (2019 ed.). SPECTRUM. > Chapter 12: Era of Militant Nationalism (1905-1909) > The Congress's Position > p. 263
3. [3] Rajiv Ahir. A Brief History of Modern India (2019 ed.). SPECTRUM. > Chapter 12: Era of Militant Nationalism (1905-1909) > Split Takes Place > p. 274