A. Yy Rr X Yy Rr B. YyRR X YyRR C. YYRr X YYRR D. YYRR X YYRR E. YYRr X YYRr B15. A cross between two pea plants, both of which grew from yellow, round seeds gave the following numbers of seeds: 156 yellow, round 54 yellow, wrinkled What are the genotypes of the parent plants? A. Yy Rr X Yy Rr B. YyRR X YyRR C. YYRr X YYRR D. YYRR X YYRR E. YYRr X YYRr B15. Given the following cross: Aa Bb X aa Bb where both genes are independently assorting and capital letters represent alleles which are completely dominant to lower case letters, what is the probability of obtaining progeny which exhibit either dominant phenotypes for both genes or recessive phenotypes for both genes?