Concept:In
Drosophila, the wild-type red eye color is an X-linked dominant trait, while the mutant white eye color is X-linked recessive.
Solution:- The cross is between a White-eyed male (\(X^w Y\)) and a True-breeding wild type Red-eyed female (\(X^{W+} X^{W+}\)).
- Females (\(X^{W+} X^w\)): Inherit a dominant red allele from the mother. They will all have red eyes.
- Males (\(X^{W+} Y\)): Inherit a dominant red allele from the mother and a Y from the father. They will all have red eyes.
- Therefore, all males and females will be red-eyed.
Why other options are incorrect:- Because the mother is homozygous dominant for the trait, she provides a dominant red allele to every single offspring, completely masking the father's recessive white allele.
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