Question

what alternate form of genes do nucleic acids have that allows them to offer variability?
allele
codon
nucleotide
chromosome

Explanation:

An allele is an alternate form of a gene. Codons are sequences of three nucleotides in mRNA that code for amino acids. Nucleotides are the building blocks of nucleic acids. Chromosomes are structures that contain DNA (a nucleic acid). Since the question asks for the alternate form of a gene, allele is the correct term.

Answer:

allele