Human Embryos Have a Developmental Stage During Which They Have

Multiple Choice

Human embryos have a developmental stage during which they have a tail and pharyngeal pouches (those pouches develop into gills in fish) .How can we explain these characteristics of human embryos?

A) Human embryos need a tail and gills to breathe during development in the placenta.
B) Human embryos spend time in the water where tails and gills are useful.
C) Human embryos share a common ancestor who had gills.
D) Both A and B are correct.