Answer:
the gene for yellow body and the gene for forked bristles
Step-by-step explanation:
The two genes that will have the highest recombination frequency are the gene for yellow body and the gene for forked bristles.
Gene recombination refers to the exchange of genetic materials between different gene-containing regions (loci) on the same chromosome or between two or more independent chromosomes. A linkage map shows the frequency of recombination between genes.
Generally, on a linkage map, when two loci are close to one another on the same chromosome, the frequency of recombination of the genes would be less than that of two loci that are further apart. In other words, the closer the loci, the lower the frequency of gene recombination and vice versa.
In this case, the distance between the genes for yellow body and tan body is 27.5 map units, yellow body and sable body is 43 map units, yellow body and forked bristles is 56.7 map units. The genes for yellow and forked bristles are the furthest to each other with 66.7 map units and, as such, will have the highest recombination frequency.