Answer:
Comparative anatomy.
Explanation:
Comparative anatomy is a branch of science in which we study about similarities and differences present in different organisms. This type of study is very important for the classification of living organisms. Comparative anatomy tells us about the evolution of an organism. Scientists study DNA, embronic structure and the internal structure of species to see the evolution of different organisms.
Hi!
It would be D, because trilobites were aquatic.
Hope this helps!
