c replaces g. does not cause a frameshift mutation so it is not insertion or deletion, and i have no clue what corruption is when there is the word "replace" it is probably substitution.
Mutation refers to a change in the genetic sequence of an organism. Mutation can be of different types depending on how it occurs. A type of mutation called SUBSTITUTION MUTATION involves the replacement of a nucleotide base by another in a gene.
For example, as stated in this question, when a cytosine (C) replaces a guanine (G) in a strand of DNA, it is called SUBSTITUTION MUTATION because guanine base replaces cytosine base in the sequence.