Concept:Subsistence farming is a system where the produce is meant only for the family's own consumption.Explanation:When farmers grow crops and rear animals only to meet the needs of their own family, the system is called subsistence farming.The output is not meant for sale or commercial trade.It is focused on survival and self-sufficiency rather than generating profit.Therefore, among the given options, this practice is best termed subsistent farming.Answer:D. subsistent farming