A sounds correct
Please vote answer branliest! Thanks.
Answer:
A homologous pair
Explanation:
In determining the expression trait of humans, this is based on the homologous chromosomes. This in turn comprised of alleles otherwise known as homologous alleles. The homologous loci are thereby located in these alleles which served as the formation of traits when combined.
Hence, normally, A HOMOLOGOUS PAIR is required to determine the outward expression of a trait?
Answer:
organ level
Explanation: because multiple types of tissues are working together.