Which one of the following is a filter feeder?

a) Catfish

b) Octopus

c) Oyster

d) Pelican

13. Ans: c

Explanation:

Filter feeders:

Filter feeders are aquatic animals that obtain food by straining particles and small organisms out of water. They do this by moving through the water or taking advantage of water moving by them. Filter feeders typically pass water over a specialized filtering structure.
They use various filamentous structures to capture food particles from the water, such as bristles, cilia, or tentacles, by creating feeding currents or acting as sieves to intercept particles from suspension passing through.
Oysters are filter feeders, belong to mollusks that remove plankton, bacteria and toxins from the water and even increase ecosystem health.
They can remove excess nitrogen and nitrates from water and incorporate it into their shells and tissue.
Near oyster reefs, the water is often clearer.
Some other filter feeders in nature include mussels, clams, krills, baleen whales, mollusks, sponges, flamingos, a few species of ducks and geese, manta rays, whale sharks (the largest fish in the world) and basking sharks.

Hence, option c is correct.