On a normal ordered chromsome, two loci, a and b, lie 15 map units apart on the left arm of a metacentric chromosome. A third locus, c, lies 10 map units to the right of b on the right arm of the chromosome. What frequency of progency phenotypes do you expect to see in a testcross of an a b c/a+ b+ c+ individual if the a+ b+ c+ chromosome

a. has normal order
b. has an inversion with breakpoints just proximal to a and just distal to b
c. has an inversion with breakpoints just proximal to a and just proximal to c
d. has an inversion with breakpoints just distal to a and just distal to c