In pea plants, the gene for the color of the seed has two alleles. In the Punnett square shown below, the dominant allele (Y) represents yellow and the recessive allele (y) represents green.

Punnett Square showing a grid that is blank with 4 empty boxes, two columns and two rows. The female parent plant across the horizontal side, top, of the grid indicates a yellow phenotype and a genotype of Yy. The male parent plant along the vertical side of the grid indicates a yellow phenotype and a genotype of YY.

Based on the Punnett square, what percentage of offspring would have genotype YY?

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