Answer:
Option D, comparative anatomy
Step-by-step explanation:
Anatomy is the branch of science in which the body structure of an organism is studied.
Comparative anatomy is a sub branch of Anatomy in which the body structure of different organisms (including plants and animals) is assessed and studied to understand the physical changes undergone during the process of evolution.
Generally, similar body structures of different species is compared to understand the adaptive changes that they have undergone during the process of evolution.