Question

what is the functional unit of heredity? gene mrna codon dna i dont know yet

Explanation:

In biology, the functional unit of heredity is a gene. Genes are segments of DNA that code for a specific trait or function. mRNA (messenger RNA) is involved in protein synthesis, a codon is a sequence of three nucleotides in mRNA that codes for an amino acid, and DNA is the molecule that contains genes but the functional unit of heredity itself is the gene.

Answer:

A. Gene