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Select the TWO answer choices that, according to paragraph 4, indicate two methods people used to increase the productivity of their land. To receive credit you must select TWO answers A. They planted different crops in different sections of the farm each year. B. They used improved irrigation methods to increase the yield of crops. C. They increased the use of fertilizers to supply more nutrients to plants. D. They used new horticultural practices to produce different varieties of plants in the same section of the farm.