Question

1. which kind of symmetry is shown by an adult echinoderm?

• bilateral
• asymmetrical
• triradial
• radial

Explanation:

Echinoderms (like starfish, sea urchins) in adulthood exhibit radial symmetry, meaning body parts are arranged around a central axis (e.g., 5 - fold symmetry in many). Bilateral is two - sided, asymmetrical has no symmetry, triradial is three - fold (not typical for adult echinoderms). So the correct option is radial.

Answer:

D. radial