In pea plants, the allele for purple flowers, P, is dominant over the allele for white flowers, p. Which conclusion about phenotype and genotype is possible?
If a plant has purple flowers, then its genotype must be Pp.
If a plant has white flowers, then its genotype must be Pp.
If a plant has purple flowers, then its genotype must be PP.
If a plant has white flowers, then its genotype must be pp.