Which statement correctly describes the role of chance in evolution? a. evolutionary change proceeds by an accumulation of changes that occur by chance. b. an allele that increases evolutionary fitness cannot be lost from a population by chance events. c. the ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism's dna

c. The ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism's DNA

Explanation:

Mutations are changes in DNA sequence that can create genetic variation within the population. Mutations are important for evolution because of their ability to form a new genetic variant (allele) that can be spread to the offspring.  If a new variant of a trait formed by a mutation is advantageous and helps the organism to survive and reproduce,  it is going to be favourable by natural selection. That  variation will more likely be passed to the next generation and remain over time.