Bipinnaria is larval stage ofA. AsteroideaB. HolothuroideaC. EchinoideaD. Crinoidea

The correct answer is A. Asteroidea.

Here’s a detailed explanation:

Bipinnaria is a specific type of larval stage that occurs in certain echinoderms. Echinoderms are a group of marine invertebrates that include sea stars (starfish), sea urchins, sea cucumbers, and sea lilies.

Asteroidea is the class that includes sea stars. The bipinnaria larva is characteristic of sea stars. The bipinnaria stage is a bilateral, free-swimming larva that eventually develops into the adult form, which is radially symmetrical.

Holothuroidea refers to sea cucumbers, which have a different larval form called the auricularia larva, not bipinnaria.

Echinoidea refers to sea urchins and sand dollars, which have the echinopluteus larval stage, also different from bipinnaria.

Crinoidea refers to sea lilies and feather stars, which have a completely different larval stage known as the Doliolaria, not bipinnaria.

Thus, the bipinnaria larva is specific to the class Asteroidea.