Which is a frame shift mutation

Frameshift mutation changed the reading frame which can be caused by insertion or deletion

A frame shift mutation is a genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read.

Explanation:

because, A DNA sequence is a chain of many smaller molecules called nucleotide. Frame shift mutations are produced by molecules that can insert between the normal bases to create mistakes during DNA synthesis. These are usually flat molecules, such as the acridness dyes, that have a hydrophobic nature (remember that hydrophobic base stacking is a contributing force in the structure of the helix). A frame shift mutation is produced either by insertion or deletion of one or more new bases.