What type of DNA mutation is this?
Original strand: A-T-C-G-T-A-G-G-C-T-A-G
Mutated strand: A-T-C-G-A-T-A-G-G-C-T-A-G

A.) nucleotide insertion
B.) trinucleotide repeat
C.) single nucleotide substitution (point mutation)
D.) nucleotide deletion