The correct answer is option 'D', Debendra Nath Tagore.

Debendra Nath Tagore was a prominent figure in the Bengal Renaissance and played a key role in the socio-cultural and educational reforms of the time. He established the Tattvabodhini Sabha in 1839 in Calcutta (now Kolkata).

Establishment of Tattvabodhini Sabha:
The Tattvabodhini Sabha was established by Debendra Nath Tagore along with a group of like-minded individuals with the objective of promoting social, educational, and cultural reforms in colonial Bengal. The Sabha aimed to revive and propagate the ancient knowledge and wisdom of India and promote a sense of national identity among the people.

Objectives of Tattvabodhini Sabha:
1. Educational Reforms: The Sabha focused on promoting education among the masses, especially in the vernacular languages. It aimed to establish schools and colleges to provide modern education to both boys and girls.

2. Social Reforms: The Sabha aimed to address social issues such as the abolition of sati (the practice of widows self-immolating on their husband's funeral pyre), child marriage, and the caste system. It advocated for women's rights and sought to improve the condition of women in society.

3. Cultural Revival: The Sabha aimed to revive and promote Indian art, literature, music, and philosophy. It encouraged the study of ancient scriptures and texts and sought to integrate traditional knowledge with modern ideas.

Activities of Tattvabodhini Sabha:
1. Publication of Jnananvesan: The Sabha published a monthly journal called Jnananvesan, which aimed to disseminate knowledge and spread awareness among the masses. It covered a wide range of topics, including literature, science, history, and social issues.

2. Educational Initiatives: The Sabha established schools and colleges to provide modern education to both boys and girls. It emphasized the importance of education in empowering individuals and creating a more enlightened society.

3. Social Reforms: The Sabha actively campaigned against social evils such as sati, child marriage, and the caste system. It organized public meetings, debates, and discussions to raise awareness and mobilize public opinion against these practices.

Impact of Tattvabodhini Sabha:
The establishment of the Tattvabodhini Sabha marked a significant turning point in the history of Bengal Renaissance. It played a crucial role in promoting education, social reforms, and cultural revival in colonial Bengal. The Sabha's efforts laid the foundation for the future social and educational reforms in the region and contributed to the overall awakening of Indian society.

In conclusion, Debendra Nath Tagore established the Tattvabodhini Sabha in 1839 in Calcutta with the aim of promoting education, social reforms, and cultural revival. The Sabha played a crucial role in the Bengal Renaissance and had a lasting impact on the socio-cultural fabric of colonial Bengal.