Final answer:
When a recessive (aa) organism is crossed with a wild-type (A+) organism that has a deletion of the region where the locus of the wild-type (A+) gene lies, the resulting offspring will have the genotype Aa and exhibit the wild-type phenotype, assuming the wild-type gene is non-essential.
Step-by-step explanation:
When a recessive (aa) organism is crossed with a wild-type (A+) organism that has a deletion of the region where the locus of the wild-type (A+) gene lies, the outcome depends on whether the wild-type (A+) gene is essential for survival. If the wild-type (A+) gene is not essential, then the resulting offspring will have the genotype Aa and will exhibit the wild-type phenotype.
However, if the wild-type (A+) gene is essential for survival, the resulting offspring will all have the genotype Aa and exhibit the wild-type phenotype, as the recessive allele (a) cannot compensate for the loss of the wild-type gene. Therefore, all resulting offspring would display the recessive phenotype associated with the aa genotype, assuming no other complicating factors are involved.