Which is an example of using comparative anatomy to study evolutionary relationships? comparing and contrasting the dna of two organisms studying the digestive system structure in two organisms using ancient footprints to learn about an organisms behaviors looking at the development of a fertilized egg of an organism?

The answer is comparing and contrasting the dna of two organisms

Comparing Anatomy: Shows how natural selection can change parts of organisms' function to fit its environment.

Comparing Embryos: Shows similar development in embryos in many species, which shows how all organisms descended from a common ancestor.

Comparing Biochemistry: All life uses DNA, use the same 20 amino acid in proteins, use glucose for energy, which explains that life had the same ancestor.