The correct answer is option c. "frameshift mutations".
Explanation:
The reading frame of a gene is based on base-pair triplets, starting from the start codon until the ribosome encounters with the end codon. Base-pair additions and deletions are collectively referred to as frameshift mutations because they alter the reading frame of the gene. Base-pair additions and deletions break down the original sequence of the gene triplets, which alters the open reading frame and usually results in the production of non active proteins.
The cell must replicated DNA because when the cell divides, the daughter cells must have identical copies of DNA. DNA replication occurs in the S phase during interphase of the cell cycle.