Final answer:
The only possible allele combination that can be passed on to the offspring due to independent assortment from a genotype of yyrr is 'yr'. This is because the genotype is homozygous for both genes, with no alternative alleles present.
Step-by-step explanation:
The question is asking for all of the possible allele combinations that can be passed to the offspring from the genotype yyrr due to independent assortment. According to Mendel's law of independent assortment, each gamete (sperm or egg) gets one set of alleles for each gene, and the sorting of alleles into gametes is random. Since the genotype yyrr is homozygous for both genes (meaning both alleles for each gene are the same), the only possible gamete combination is yr. As a result, the correct answer would be:
Regardless of the random assortment, each gamete from an individual with a yyrr genotype will always have the same allele combination of yr because there are no alternative alleles present for either gene.