Sponges are mostly(a) Radial(b) Biradial(c) Asymmetrical(d) Bilateral

The correct answer is (c) Asymmetrical.

Explanation: Sponges belong to the phylum Porifera. Unlike many other animals, sponges do not have a definite shape or symmetry. Their bodies are asymmetrical, meaning they do not exhibit symmetry like radial, biradial, or bilateral symmetry seen in other animals.

Radial symmetry: Found in animals like jellyfish, where the body parts are arranged around a central axis.
Biradial symmetry: Seen in some animals, where the body can be divided into two similar halves along two planes.
Bilateral symmetry: Found in animals like humans, where the body can be divided into two identical halves along one plane.
Sponges, however, do not follow any of these symmetries and are considered asymmetrical. They have an irregular shape and their body structure is adapted to their simple lifestyle, filtering water through numerous pores.