This is a sub-list of activity codes from the Income Tax website. Clearly, there has been an attempt to list out specified professions (falling u/s 44AA):
0601 Professionals [Chartered Accountants, Auditors, etc.] 0602 Professionals [Fashion designers] 0603 Professionals [Legal professionals] 0604 Professionals [Medical professionals] 0605 Professionals [Nursing Homes] 0606 Professionals [Specialty hospitals] 0607 Professionals [Others]
0701 Service Sector [Advertisement agencies] 0702 Service Sector [Beauty Parlours] 0703 Service Sector [Consultancy services] 0704 Service Sector [Courier Agencies] 0705 Service Sector [Computer training/educational and coaching institutes] 0706 Service Sector [Forex Dealers] 0707 Service Sector [Hospitality services] 0708 Service Sector [Hotels] 0709 Service Sector [IT. enabled services, BPO service providers] 0710 Service Sector [Security agencies] 0711 Service Sector [Software development agencies] 0712 Service Sector [Transporters] 0713 Service Sector [Travel agents, tour operators] 0714 Service Sector [Others]
Full list : https://incometaxindiaefiling.gov.in/eFiling/Portal/StaticPDF/List_Of_Useful_Codes.pdf?0.1419578540147739