Embryo of a turtle, mice and human show:

Explanation

The embryos of turtles, mice, and humans illustrate the concept of comparative embryology, which studies the similarities and differences in the embryonic development across various species. During the early stages, these embryos exhibit features common to all vertebrates, suggesting a shared evolutionary history. This evidence supports the idea of a common ancestor from which these species diverged. Options B, C, and D are incorrect because they either misinterpret the context of embryonic development or describe concepts (distinct differences, vestigial organs, analogous structures) that do not pertain to the similarities observed in early vertebrate embryos.