Answer:
Option-A
Step-by-step explanation:
Radial symmetry refers to the symmetry in which the organism can be cut into the same half through any plane which can be observed in the organisms belonging to Cnidarians.
The organism with radial symmetry do not show a distinct head region and are considered to be passive drifters like observed in the corals, sea anemones, starfish.
Thus, Option-A is correct.