In an area of erratic rainfall, a biologist found that grass plants with alleles for curled leaves reproduced better in dry years, and grass plants with alleles for flat leaves reproduced better in wet years. This situation would lead to the following outcome: [a] Causes Genetic drift in the grass population. [b] Preserves genetic variation in the grass population. [c] Leads to Stabilizing selection in the grass population. [d] Leads to Uniformity in the grass population.