Minority has nothing nothing to do with categories.

Minority means a distinct and seperate religion from hinduism. All religion except hindu religion are minority like muslim, christian, sikh, jain, parsi, boodh, etc.

Where as category classification is based on socio economic factors certain castes within all religions like hindus, muslim, jain, sikh, christian, parsi, boodh are believed to be developed which come under forward castes , so there is no facilities from govt.

Certain caste believed to be backward comes under OBC; and OBC reservation for their upliftnent.

Certain caste are defined as deprived caste come under SC; so SC reservation for their upliftment.