Question

The common name of Aplysia is
A. Sea-mouse
B. Sea-hare
C. Sea-horse
D. Sea-fan

Answer 1

Hint: Organisms are named on the basis of their characteristics. The naming of the organism eases the process of identification of the particular organism and also helps to relate them to the closest related organisms. Identification and naming of the organism forms the basics of the study of the living organisms.

Complete answer:
A common name can be described as the name that is used in the normal layman language and it is used in everyday life. It is the frequently used name that is used as a part of traditional local or folk names. It does play an important part in the classification of the organisms but is generally not very scientific in approach. These names are provided by the local peoples which may vary from one place to another. The common names provide for an informal classification and are not based on scientific rules and conducts. On the other hand, when naming is done based on scientific basis, it is known as biological nomenclature.
Aplysia belongs to the phylum Gastropod and is included in the superfamily Aplysiidae. It is a genus of organisms that are commonly called sea-hares. They are the marine gastropods and are benthic organisms. Aplysia possess a round shaped body, two long rhinophores that are projected upwards from the head. This arrangement of the head in Aplysia resembles the ears of a hare and hence, it is commonly called sea-hare.
Aphrodite is a genus of marine polychaete worms and is commonly known as sea-mouse. It belongs to the phylum Annelida. The body is covered by numerous parapodia and setae. There are two pairs of appendages which lie close to their mouth.
Sea-horse is the common name of marine fish of genus Hippocampus. The fish is marine and the body structures do not resemble the fishes. Rather, the body with its head and neck looks like a horse and so it is commonly called a sea-horse.
Alcyonacea are commonly known as sea-fans due to the reason that the individual tiny polyps form colonies which are elaborate, erect and resemble that of a fan.

Hence, the correct answer is option (B).

Note: The common name of the organisms is a basis of informal naming that is not always based on scientific considerations. Aplysia is commonly known as sea hare. They belong to the phylum Gastropod and their head region along with the rhinophores resembles that of the hare, hence, Aplysia is commonly known as sea-hare.