Answer:
The double recombinant individuals are less frequent ---> Abc and aBC
Explanation:
We can know if genes are linked, by looking at the progeny distribution. In a tri-hybrid cross, If individuals, whose genes assort independently, are test crossed, they produce a progeny with equal phenotypic frequencies 1:1:1:1:1:1:1:1. If we observe a different distribution, meaning that phenotypes appear in different proportions, we can assume that genes are linked in the heterozygote parent.
We can recognize the parental gametes because their phenotypes are the most frequent in the descendants, while the double recombinants are the less frequent. Finally, the simple recombinant gametes are the ones with intermediate phenotypes frequencies.
In the present example, the phenotypic ratio shows different proportions than the expected ones if they were not linked.
We can recognize the parental gametes in the descendants because their phenotypes are the most frequent,
while the double recombinants are less frequent.
And simple recombinant gametes produced by the cross, which frequencies are intermediate.
a. Which phenotype represents the double crossovers
The double recombinants are less frequent ---> Abc and aBC
