The Dharma Sabha was founded by Radhakanta Deb. While the options provided include several prominent figures of the time, such as Krishna Mohan Banerjee, Keshab Chandra Sen, and Akshay Kumar Datta, it was Radhakanta Deb who established the Dharma Sabha.

Radhakanta Deb was a Bengali nobleman and religious reformer during the 19th century. He sought to preserve and promote Hindu religious practices and traditions in the face of British colonial influence. The Dharma Sabha, which translates to "Religious Society," was founded by Radhakanta Deb as a means of organizing and mobilizing Hindus in defense of their faith.

It is important to note that while the other options provided were notable figures in their own right, they were not directly associated with the founding of the Dharma Sabha. Instead, it was Radhakanta Deb who played a significant role in establishing this important Hindu organization.