(C) Only I and III
Banks and Cooperatives are formal sources of credit, supervised by the RBI. Moneylenders and businessmen are informal sources.
As per the textbook, formal sector loans include banks and cooperatives. Informal lenders include moneylenders, traders, employers, relatives, and friends. The key distinction is RBI supervision — formal lenders are regulated; informal ones are not. Eliminate II (moneylender) and IV (businessman) as both are informal sources.