A genome is an organism's complete set of DNA including all of its genes. Each genome contains all of the information needed to build and maintain that organism. This is the largest in the given options. Chromosomes are the threadlike structures located inside the nucleus of animal and plant cells. The building blocks of nucleic acids are the nucleotides. A gene is the basic physical and functional unit of heredity. Genes are made up of DNA. Thus, the correct answer is option (D), 'Genome, chromosome, gene, nucleotide'.
