The correct option is A Dr. B. R. Ambedkar
Dr. B. R Ambedkar was a great champion of labour rights. He campaigned for the benefits of labourers like reduction in factory working hours, compulsory recognition of trade unions, employment exchanges, employee state insurance, minimum wages for labourers, and ‘coal and mica mines provident fund’. Today labourers in India enjoy these benefits as a result of Dr. B. R. Ambedkar’s work.