Question

Which of the following belongs to a fish category?
A. Starfish
B. Cuttlefish
C. Devil fish
D. Seahorse

Answer 1

Unlike some other fish, they don't have teeth; conversely, they suck food via their snout. They swim vertically, lack pelvic fins, have bone plates over their bodies, and move their eyeballs totally independent.

Complete step by step answer: They are special in appearance, with a horse-like head, a prehensile tail, separately moving eyes, and a brood pouch. They've got long, tubular snouts and thin, toothless mouths. Their bodies are enclosed by successive rings of bone plates. The name of the genus comprising sea horses is derived from greek words hippos which means "horse" and kampos means "sea monster". Seahorse is a small sea fish within the Hippocampus genus. They've got a horse like a head, so called a seahorse. As it demonstrates the main characteristics of a fish called a true fish. Star fish is an Echinoderm.
Hence, the correct answer is option D.

Additional Information:
-Seahorses range in size from 2 to 35 cm in length. The smallest type, Denise's Pygmy Seahorse i.e., H. denise, and this can be found in the tropical western Pacific from Indonesia to Vanuatu. The largest type, the H. abdominalis, inhabits the waters off the coast of South Australia and New Zealand.
-The reproductive activity of seahorses is remarkable in that the male holds the fertilised eggs. After an extensive courtship, the female uses an ovipositor which is egg duct to place her eggs in a brood pouch on the base of the male's tail, at which eggs are later fertilised.

Note: Seahorses are somewhat immobile, swimming more slowly than most fish. They hold a vertical position when swimming and push themselves forward using a soft-rayed dorsal fin. They use pectoral fins on the side of the head to navigate. Some scientists claim that this upright swimming pose evolved shortly after the expansion of seagrass in the western Pacific, some 25 million years ago.