Answer: The correct answer for the blanks are-
1) an insertion mutation.
2) This mutation won't alter the protein function.
Muttation can be described as a permanent change in the genetic material ( that is deoxyribonucleic acid, DNA) of an organism.
Insertion mutation is one of the types of mutation in which there is an addition of one or more nucleotide bases in the already existing DNA sequence.
In this question, Cytosine ( C) is inserted at the fourth position of already existing DNA sequence.
As this mutation has occurred in the non coding region ( a region of DNA sequence that does not code for any protein) according to the question, therefore, this mutation will not interrupt the formation of a functional protein.