The correct answer is B. Incomplete dominance
Step-by-step explanation:
In genetics, incomplete dominance occurs as two alleles (forms of genes) lead to a new phenotype because there is no dominance or complete expression of one of the alleles but a combination of both. Incomplete alleles can be seen in the case presented because the alleles that determine color in the flowers have combined, this means neither the allele that leads to blue flowers nor the allele that leads to yellow flowers express completely but both combine; this is the reason the offspring have green flowers as blue and yellow lead to blue color.