The relative frequency of an allele is

A. the total number of copies of an allele in a gene pool.
B. all the genes that are present in a the gene pool of a population.
C. the number of times that the allele occurs in a gene pool, compared with the number of times other alleles for the same gene occur.
D. the number of times that dominant alleles occur in a gene pool compared with the number of recessive alleles.