Which hereditary rule explains why a self-fertilizing parent that is heterozygous for the a locus (aa) can produce offspring that are aa or aa?
a. principle of independent assortment
b. codominance
c. dominance
d. principle of segregation

During gamete formation, genes segregate (separate) from each other, so it can produce all possible offspring (according to Mendel's law of segregation)

In short, Your Answer would be Option D

Hope this helps!

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