Q. Whose branch of Brahmo Samaj was still known as Adi Brahmo Samaj after the spilt in 1866?
Answer: Debenandra Nath Tagore's
Notes: Debendranath’s Samaj henceforth came to be known as the Adi Brahmo Samaj. Due to Keshab Chandra Sen's liberal and cosmopolitan outlook brought about a split in the Brahmo Samaj in 1866.

This question is part of West Bengal General Studies Course on GKToday Android app.