Concept:It is a farming system where land is cultivated briefly and then left for a fresh area.Explanation:Crop rotation involves growing different crops in sequence on the same land.Mixed cropping means growing two or more crops at once on the same field.Shifting cultivation matches the practice described: using land for some years, then abandoning it for new land.Ley farming alternates crops with a grass or legume fallow period on the same land.Therefore, the system described in the question is shifting cultivation.Answer:C. Shifting cultivation