Ahorticulturalist wants to produce geraniums with specific characteristics. she knows that the trait of red flowers is governed by the allele r (rr and rr) and the trait of white flowers is governed by the allele r (rr) . the horticulturalist plans to cross a geranium that is true-breeding for red flowers with a geranium that is true-breeding for white flowers. which punnett square best describes that cross?