The correct answer is: Punett square C.
A true-breeding organism or a purebred is by Mendelian genetics organism that is homozygous (the pairs of allels are the same) for the trait.
In this case, a geranium that is true-breeding for red flowers (dominant homozygous) is crossed with a geranium that is true-breeding for white flowers (recessive homozygous), resulting in offspring, all with heterozygous genotype.
