Question

which adaptation arose several times throughout evolutionary history? select one answer.
pseudocoelom
radial symmetry
tissues
bilateral symmetry

Explanation:

Radial symmetry is shown to have evolved multiple times in the diagram. Cnidarians have radial symmetry, and then echinoderms (which are more complex in other aspects like being deuterostomes) also have radial symmetry. This indicates that radial symmetry arose more than once in evolutionary history. Pseudocoelom, tissues, and bilateral symmetry each seem to have a single - point of origin in the given diagram.

Answer:

Radial symmetry