In: Biology
(A) +/+ X w/w
(B) +/w X w/w
(C) +/w X +/w
(D) w/w X w/w
+ is the dominant allele and w is the recessive allele
So wherever, + is present, it will express regardless of presence of the other allele. The crossovers are drawn in the image below. And the ratios (round:wrinkled) are mentioned under
A. Phenotype: all peas will be round, Genotype: +w
B. Phenotype: 1:1, Genotype: 1:1
C. Phenotype: 3:1, Genotype: 3:1
D. Phenotype: all wrinkled. Genotype: ww