What was the main reason for the split in the Indian National Congress at Surat in 1907?

The correct answer is B. At Surat in 1907, the clash was between the moderates, who believed in petitions, prayers and gradual constitutional reform, and the extremists led by Tilak, Lajpat Rai and Bipin Chandra Pal, who had little faith that the British would concede anything through negotiation. The dispute was over methods and goals, especially swaraj versus self-government within the Empire. The session broke down into disorder and the Congress split, with the moderates in control until the 1916 Lucknow Pact reunited the two wings.

• A is wrong on chronology: communal electorates came with the Morley-Minto Reforms of 1909, two years after Surat.
• C is wrong: the All India Muslim League was founded at Dhaka in December 1906 and had no role in the Surat split.
• D is wrong: Aurobindo Ghosh was not a presidential contender at Surat; Rash Behari Ghosh was chosen as a compromise president.

Mains angle: the split shows the Congress as an elite body of petitioners before it became a mass movement under Gandhi after 1915.

Trap: candidates pick C because the Muslim League and the Surat split fall in the same decade, and they assume communal politics caused the rift. The split was internal to Congress and about methods.