The correct option is A Morarji Desai
The Mandal Commission, or the Socially and Educationally Backward Classes Commission (SEBC), was established in India on 1 January 1979 by the Janata Party government under Prime Minister Morarji Desai with a mandate to "identify the socially or educationally backward classes" of India. Hence, Option A is correct. The rest of the prime ministers did not take part in formulating the Mandal Commission, hence, incorrect.