39. Which characteristic represents a synapomorphy uniting ecdysozoans (e.g., arthropods and nematodes) and most clearly distinguishes them from other bilaterian invertebrates?
(A) Presence of a fluid-filled body cavity
(B) Expression of radial body symmetry
(C) Periodic molting of an external cuticle
(D) Development of repeated body segments
(E) Possession of an open circulatory system
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統計: A(1), B(1), C(4), D(0), E(1) #3852893
統計: A(1), B(1), C(4), D(0), E(1) #3852893