For appointing employees in a co-operative society, the Managing Committee (A) is generally the competent authority, as they manage day-to-day affairs, though the Registrar (D) or Government (C) can intervene or provide guidelines, especially in specific cases or under certain conditions, with the final power resting with the General Body (B) for major decisions. So the most fitting answer is (A) Managing Committee, but often with oversight from the Registrar/Govt.
Managing Committee (A): This elected body handles daily management and usually has the power to appoint staff, as per bye-laws.