Answer:
Alleles.
Explanation:
Gene may be defined as the functional segment of DNA that codes for the particular protein. Genes are responsible for the phenotype and genotype of the organism. Each gene may exist in multiple forms.
The variants forms of the genes are known as alleles. Alleles are the alternative form of the same gene. A single gene may have atleast two alternative form. These alternative forms together contribute the functional aspect of the organism.
Thus, the correct answer is alleles.
