Which of the following best defines alleles?

Alleles are different forms of the same gene, which is essential in understanding genetics and inheritance. Each gene can exist in various versions, called alleles, which can lead to different traits being expressed. For example, in the case of a gene responsible for flower color, one allele might produce red flowers while another might produce white flowers. This variation is crucial in genetics as it explains why individuals may express different characteristics even though they belong to the same species.

Identifying alleles as different forms of the same gene also helps clarify how traits are inherited from parents to offspring. Each parent contributes one allele for a gene, and the combination of these alleles determines the offspring's traits. This understanding is fundamental to the study of dominant and recessive traits, as well as the formation of phenotypes in organisms.

The other options refer to concepts that do not accurately describe alleles. Identical copies of genes pertain to when there are no variations present, which does not capture the essence of alleles being distinct forms. Non-coding regions of DNA relate to segments that do not code for proteins and do not usually have an effect on traits. Lastly, segments that do not affect traits are not relevant to the definition of alleles, as alleles specifically