Among protostomes, which morphological trait has shown the most variation?

Question

A. Type of symmetry (bilateral vs. radial vs. none)
B. Type of body cavity (coelom vs. Pseudocoelom vs. acoelom)
C. Number of embryonic tissue types (diploblastic vs. triploblastic)
D. Cephalization (head vs. no head)

I think it is B but can someone please confirm it for me???

Answer 1

It's B