`Tattvabodhini Sabha` was indeed established by Devendranath Tagore in the year 1839. This organization was instrumental in the religious, social and literary reform movements of the time. This Sabha played an important role in the propagation of Brahmo Samaj, which stood against social evils like sati and advocated for women rights, education and against caste discrimination.
Option 2 suggests Kesab Chandra Sen established the Sabha in 1857, which is incorrect as he joined the Brahmo Samaj, which was supported by Tattvabodhini Sabha, but he didn`t establish it.
Option 3 mentions Akshay Kumar Datta as the founder in 1850, but Datta was a significant associate of the Tattvabodhini Sabha, not the founder.
Option 4 claims that it was established by Dwarakanath Tagore in 1840. This is also incorrect because though Dwarakanath was a prominent figure in the Brahmo Samaj, he was not the founder of Tattvabodhini Sabha.
Therefore, Devendranath Tagore in 1839 (option 1) is the correct answer.