11. About genetic mutation, which of the following statement is TRUE?
(A) Silent mutations usually do not have observable effects on phenotypes becausethey are in-frame mutations
(B) Missense mutations change a codon into a stop codon leading to a truncatedprotein
(C) Nonsense mutation is a point mutation in which a single nucleotide changeresulted in a change in an amino acid
(D) Insertions and deletions are additions or losses of nucleotides in a gene thatusually alter the reading frame producing frame-shifted mutations