Concept:In
Drosophila, eye color is an X-linked trait where red eyes (wild type, \(X^{W+}\)) are dominant over white eyes (mutant, \(X^w\)).
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 offspring (\(X^{W+} X^w\)): Inherit a dominant red allele from the mother and a recessive white allele from the father. They will all have red eyes (carriers).
- Male offspring (\(X^{W+} Y\)): Inherit the Y chromosome from the father and a dominant red allele from the mother. 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, she guarantees a dominant red allele to all her offspring, masking any recessive allele passed by the father.
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