The social reformer who founded the SNDP Yogam was:

Ayyankali
Sree Narayana Guru
Chattampi Swamikal
Vaikunta Swamikal

The correct answer is B) Sree Narayana Guru.

Sree Narayana Guru was a social reformer, religious leader, and poet from Kerala, India. He is considered one of the most important figures in the history of Kerala. He is best known for his work to uplift the Ezhava community, a lower caste in the Hindu caste system. He founded the Sree Narayana Dharma Paripalana Yogam (SNDP Yogam), an organization that worked to improve the social and economic conditions of the Ezhava community. He also founded a number of schools and temples for the Ezhava community.

Ayyankali was a social reformer who worked to uplift the Dalit community in Kerala. He is best known for his work to abolish the practice of untouchability. He also founded a number of schools and hostels for the Dalit community.

Chattampi Swamikal was a social reformer and religious leader from Kerala. He is best known for his work to reform Hinduism. He founded the Brahma Samaj, an organization that worked to promote monotheism and social reform within Hinduism.

Vaikunta Swamikal was a social reformer and religious leader from Kerala. He is best known for his work to promote education and social reform among the Ezhava community. He founded a number of schools and temples for the Ezhava community.