Which one of the following types of mutations can lead to a major change in the encoded protein?
A. Insertion of a single nucleotide near the end of the coding sequence.
B. Removal of a single nucleotide from the beginning of the coding sequence.
C. Deletion of three consecutive nucleotides of a codon in the middle of the coding sequence.
D. Deletion of four consecutive nucleotides in the middle of the coding sequence.