The accompanying figure shows the results of Jackson and Cheetham's studies on fossil and living cheilostome bryozoans.What can you infer from these diagrams?

A) Species of bryozoan have tended to persist with very little morphological change.
B) Bryozoans have unusually low genetic diversity.
C) Bryozoans predominantly evolve by phyletic transformation, or anagenesis.
D) Bryozoans have suffered heavily from extinction events on islands.
E) It is hard to define bryozoan species because of the presence of so many intermediate forms.