Sarah performs an experiment to determine the effect of nitrogen on plants. she studies the effect of nitrogen on the growth of the root hair, height of the plants, and nodule formation. which factor is an independent variable? a) amount of nitrogen b) growth of root hair c) nodule formation d) height of the plants

What is the best conclusion based on this data? the hypothesis was not supported because the data indicated that fertilizing plants does not improve plant growth. the hypothesis was supported; to get the best growth, use 5 milliliters of fertilizer per plant. the hypothesis was not supported; the data indicated that too much fertilizer can inhibit plant growth. the hypothesis was supported; to get the best growth, use 15 milliliters of fertilizer per plant.