Suppose the A and B genes are on the same chromosome but separated by $75$ map units. What fraction of

the progeny from the cross AB$/$ab $$ ab$/$ab would be phenotypically Ab $($genotype $=$ A$\_$bb$)?$

A$)25\%$

B$)37\mathrm{.}5\%$

C$)50\%$

D$)75\%$

E$)$ None of the above.