Question

Sepia and Nautilus are the members of which class?
A. Scaphopoda
B. Cephalopods
C. Gastropoda
D. Monoplacophora

Answer 1

Hint:Sepia is a genus of cuttlefish in the lineage Sepiidae as well as it is a class Cephalopoda. Nautilus is a genus of cephalopods in the kingdom of Nautilidae. Cephalopods are the largest group of grade Mollusca.

Complete answer: Option- A – Scaphopoda
The tusk bombs or tooth shells, technically the Scaphopoda, are units of a class of shelled marine mollusc along with its worldwide distribution, along with it is the barely a category of entirely infaunal marine molluscs. The Shells of a sample within this class spectrum from about 0.5 to 15 cm in length.
Option – B – Cephalopods
A cephalopod is any component of the molluscan grade Cephalopoda like a squid, octopus, cuttlefish, or nautilus. These entirely marine animals are characterised by bilateral body proportion, a well-known skull, and a set of arms or tentacles amended from the fundamental molluscan foot.
Option – C – Gastropoda
The gastropods, naturally called snails and slugs, belong to a huge taxonomic family kingdom of invertebrates within the phylum Mollusca known as Gastropoda. This category includes snails and slugs from saltwater, from freshwater, as well as from the land.
Option – D – Monoplacophora
Monoplacophora, which means "bearing one plate", is a polyphyletic superclass of molluscs with a cap-like shell. Currently living at the underside of the deep sea.

So, the right answer to the provided question is Option – B “Cephalopods”.

Note: Cephalopods evolved as a prominent during the Ordovician period, which was exemplified by primitive nautiloids. The category presently comprises two, only distantly related, extant subclasses: Coleoidea, that further covers animals like octopuses, squid, and cuttlefish; and Nautiloidea, affected by Nautilus and Allonautilus.