The correct option is
A Jellyfish, coral, anemone, starfish
Jellyfish, corals, sea anemone all belongs to phylum Cnidaria. However, Starfish belongs to phylum Echinodermata.
Tunicates, birds, sharks, man, as all of them, belongs to Phylum Chordata.
Bats, dogs, cats, sloths again all belongs to phylum Chordata and that too all of them belongs to class Mammalia.
Liver fluke, Planaria, tapeworm and flatworm all of them belongs to phylum Platyhelminthes.
Clam, squid, nautilus and snail all of them belongs to phylum Mollusca. Thus, the correct answer is option A.