A particular plant can have red or white flowers. Assume that flower color is determined by a single gene and that the allele for red flowers (R) is dominant over the allele for white flowers (r). In a cross between two plants heterozygous for red flowers, what percentage of the offspring can be expected to have red flowers? A. 75%
B. 50%
C. 0%
D. 25%
E. 100%