Which of the following is the most likely effect of the mutation at nucleotide position 7 in the GULO gene of humans? A. The mutation results in the deletion of the GULO gene, so no polypeptide can be translated. B. The deletion of the single nucleotide causes a frame shift, changing the primary structure downstream of the mutation and resulting in a nonfunctional protein. C. The point mutation causes a substitution of the amino acid isoleucine (lle)for histidine (His) at position 7, resulting in a protein with higher than normal activity. D The substitution of a single nucleotide in the GULO coding region results in a stop codon. This results in a smaller nonfunctional protein.