Answer:
Silent mutation.
Step-by-step explanation:
Mutation is defined as the changes in a DNA sequence, and they are causing by the environmental factors such as radiation, cigarette smoke or other type of DNA damage.
Silent mutation is a type of mutation which is present in the coding region of a gene that doesn't change the amino acid sequence of the protein which is made. In the case of silent mutation there are no changes occurs in amino acid and no effect on the organism. They are also called as specific type of neutral mutation.
So, the answer is silent mutation.