5) A gene normally expresses a 150-amino acid-long protein. A point mutation occurs in the coding DNA of this protein, resulting in the production of an abnormal protein with 121 amino acids. What is this mutation type referred to as? (A) A silent mutation. (B) A nonsense mutation. (C) A missense mutation. (D) Conversion of a stop codon into Methionine codon. (E) Insertion of three nucleotides in the promoter region.