Solution:The founder of ‘Brahmo Samaj of India’ (Bhartiya Brahmo Samaj) was Keshav Chandra Sen. Devendra Nath stripped the title of ‘Acharya’ from Keshav Chandra in 1865. Hence Keshav Chandra Sen came out from original Brahmo Samaj and group under the influence of Devendra Nath Tagore called themselves as ‘Adi Brahmo Samaj.’ The group under the leadership of Keshav Chandra Sen called themselves as "Bhartiya Brahmo Samaj" or ‘Neo Brahmo Samaj.’ Again in 1878, ‘Navin Brahmo Samaj’ was further divided when Keshav Chandra Sen got married her under 14-year-old daughter with the king of Kooch, Bihar. To oppose his action, Anand Mohan Bose and Shivnath Shastri formed ‘Sadharan Brahmo Samaj.’Note: On 20 August 1828, Raja Rammohan Roy rented a house of Feringhee Kamal Bose, where he formed Brahmo Samaj. Tarachand Chakroborty was its first secretary. Devendra Nath Tagore joined this society in 1843 and Keshav Chandra Sen in 1857. Due to the difference of opinion between Devendra Nath and Keshav Chandra, on 11 November 1866, Keshav Chandra formally formed 'Bhartiya Brahmo Samaj'. Brahmos earlier established Brahmo Samaj was known as ‘Adi Brahmo Samaj’. All these details are available on the website www.thebrahmosamaj.net, Gazetteer of India (vol II: History and Culture) and Macmillan published ‘social, cultural and economic history of India’ (writer – Puri, Das, and Chopra). Later famous historians Prof. B. L. Grover and Prof. R. L. Shukla etc. in their book unknowingly described Keshav Chandra's ‘Neo Brahmo Samaj’ as ‘Adi Brahmo Samaj’. As described by famous historians, other books, and examination institutions termed Keshav Chandra Sen's group as the leader of ‘Adi Brahmo Samaj’ whereas the fact is entirely opposite. Therefore, Keshav's 'Neo Brahmo Samaj' was ‘Bhartiya Brahmo Samaj’ and basic Brahmo Samaj under the leadership of Devendra Nath was 'Adi Brahmo Samaj'.