Which one of the following has a bilateral symmetry in its body organization?

The correct answer is C. Nereis.

Bilateral symmetry is a type of symmetry in which the body can be divided into two mirror-image halves along a plane. This type of symmetry is found in many animals, including humans, insects, and fish.

A. Asterias is a starfish. Starfish have radial symmetry, which means that the body can be divided into multiple mirror-image halves along multiple planes.

B. Sea anemone is a cnidarian. Cnidarians have radial symmetry, like starfish.

D. Euchinus is a sea urchin. Sea urchins have radial symmetry, like starfish and sea anemones.

Nereis is a type of worm. Worms have bilateral symmetry.