Answer:
She can increase the amount of the fertilizer but that isnt an option and it rules out b, Soybean plants need a lot of nitrogen to survive so that rules out a, if she harvests the plants continuously then she can increase the nitrogen in the soil because the plants decompose so that makes c your answer, as for d the decomposers make it to where the nitrogen increases because of the natural nitrogen in the soil. So C is your answer.
Step-by-step explanation:
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