An organism is born with a genetic abnormality not present in any of its ancestors. This abnormality is most likely the result of?
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Genetic diseases or abnormalities can be inherited or a result of a mutation, which is a change in the nucleotide sequence in the DNA of the organism.
Mutations can happen as a result of errors during mitosis or meiosis, as well as by damage from exposure to UV radiation or a chemical substance.
So, the right answer is mutation (option A)