Explanation:

- Raja Ram Mohan Roy: He was an influential social reformer and is widely regarded as the founder of the Brahmo Samaj. In 1821, he started the Bengal weekly newspaper ‘Samvad Kaumudi’. This paper played a crucial role in promoting free thoughts and reforms.

- Aurobindo Ghosh: He was a prominent nationalist and freedom fighter. He was involved in the fight against British colonial rule but did not start ‘Samvad Kaumudi’.

- Ramkrishna Paramhans: He was a revered saint and spiritual leader in the 19th century but was not involved in journalism.

- Debendranath Tagore: He was a philosopher and religious reformer, part of the Brahmo Samaj, but didn’t initiate ‘Samvad Kaumudi’.

The correct answer is Raja Ram Mohan Roy.