Answer:
The correct answer would be deletion mutation.
Deletion is a type of mutation in which sequence of DNA or a part of a chromosome is deleted during replication of DNA.
A number of nucleotides deleted may vary from a single nucleotide to the entire length of the gene.
TTCACG should have been transcribed as AAGTGC instead of AAGGC.
The adenine present at the fourth position in parent DNA TTCACG is not replicated into the daughter strand.
It results in the deletion of thymine nucleotide from the daughter strand.
