Question

Which of the following is a crustacean?
A. Snail
B. Sea anemone
C. Hydra
D. Prawn

Answer 1

Hint: Crustaceans are a large group of animals that resemble arthropods for having an outer exoskeleton which they molt. Most of them are free-living aquatic animals with some being terrestrial. They have a segmented body divided into head, thorax, and abdomen regions.

Complete answer:
Crustaceans are mostly aquatic animals having segmented bodies with a hard outer skeleton called an exoskeleton. The body of crustaceans is divided into three regions called head, thorax, and abdomen. In some of the crustaceans, the head and thorax region may be fused to form a cephalothorax. The cephalothorax is covered by a large carapace. The crustaceans undergo molting to shed their hard exoskeletons so that they can grow in size. Each segment of crustaceans has a pair of appendages. A pair of antennae is also present at the head region. The mandibles and the maxillae form the mouthparts. The thoracic region consists of two types of legs called pereopods which are walking legs and maxillipeds which are feeding legs. The main body cavity of crustaceans forms an open circulatory system. The blood is pumped into the hemocoel by the heart. The crustaceans usually reproduce by sexual reproduction with some of them being hermaphrodites. Parthenogenesis is also observed among various crustaceans. The larval stage of crustaceans is nauplius. Some of the terrestrial crustaceans are woodlice, terrestrial crabs, etc. Most of them are aquatic like prawns, crayfish, crabs, lobsters, shrimps, etc.
So, from the above discussion, we can conclude that option D is the correct answer.

Note: Many crustacean species are consumed by humans as seafood. Crabs, lobsters, shrimp, prawns, and crawfish are the most consumed crustaceans. More than 7 million tons of crustaceans are produced by fishery per year. Also, carcinology is named as the scientific study of crustaceans.