Concept:Pisces is the superclass of true fishes, which includes cartilaginous and bony fishes.
Explanation:Dogfish belongs to class Chondrichthyes under superclass Pisces.
Chondrichthyes are cartilaginous fishes with a skeleton made of cartilage.
Examples include Scoliodon (dogfish), Pristis (sawfish), and Trygon (sting ray).
Jellyfish belongs to phylum Coelenterata, not Pisces.
Silverfish belongs to phylum Arthropoda, not Pisces.
Starfish belongs to phylum Echinodermata, not Pisces.
Thus, only Dogfish is a true fish under Pisces.
Answer:Dogfish
