Answer: B. False
Explanation:
“Hox” genes are a highly conserved group of genes, all of whose products are transcription factors bearing a specific domain (called a ”homeodomain”). The transcriptional activity of a large amount of genes relevant to embryonic development is controlled by regulatory sites which are able to bind to this domain. Changes in the transcriptional activity of even a single Hox gene may thus have dramatic downstream effects on the phenotype, as this will result in several further genes having their transcription either enhanced or suppressed.
Answer - Theory
Reasoning - Your best bet and term to describe the evolution by natural selection is theory as to still scientific theory/research is still ongoing and changes can be made in a different direction.
Organ- a group of tissues in a living organism
examples- heart, lungs, liver, kidney, and stomach