The correct answer is: A) Vaikunta Swamikal.
Vaikunta Swamikal (1852-1924) was a Hindu philosopher and social reformer who founded the Atmavidya Sangham in 1888. The Atmavidya Sangham was a society dedicated to the study of Advaita Vedanta and the promotion of social reform. Swamikal was a strong advocate for women’s rights and education, and he played a key role in the development of the Ezhava community in Kerala.
Chattambi Swamikal (1823-1891) was a Hindu philosopher and social reformer who was also a key figure in the development of the Ezhava community in Kerala. However, he did not found the Atmavidya Sangham.
Vagbhatananda (1860-1936) was a Hindu philosopher and social reformer who was also a key figure in the development of the Ezhava community in Kerala. However, he did not found the Atmavidya Sangham.
Ayyankali (1868-1941) was a social reformer who fought for the rights of the Ezhava community in Kerala. However, he did not found the Atmavidya Sangham.