Answer:
The correct answer will be option-a sequence of nucleotides in DNA that codes for a functional product.
Explanation:
A gene is the physical segment of DNA which controls one or more traits of an organism by coding the functional product.
The genes are located on the chromosomes, a highly ordered structure of DNA which embodies a number of genes encoding the various traits. These genes are present in different forms called alleles located at the locus and determine the trait by giving instructions through triplets of nitrogenous bases.
Thus, genes represent the sequence of nucleotides which codes for a functional trait.
