Concept:Darwin’s Galapagos finches provided evidence based on body structure, especially their beaks.Explanation:Darwin observed that finches on different islands had different beak shapes.Each beak type was suited to a particular feeding habit, such as cracking seeds or catching insects.These structural differences showed that the birds shared a common ancestor but had adapted over time.Since the evidence came from comparing body parts, it is classified under comparative anatomy.This supported Darwin’s idea of natural selection and evolution.Answer:A. comparative anatomy.