Animal Kingdom

The correct answer is:$ $: This group consists of jawless vertebrates, including species like hagfish and lampreys, which have bilateral symmetry rather than radial symmetry.Therefore, since Cyclostomata are bilaterally symmetrical, radial symmetry is NOT found in this taxon.

Organisms in the phylum Platyhelminthes (flatworms) are triploblastic, meaning they have three germ layers (ectoderm, mesoderm, and endoderm), acoelomate, meaning they lack a true body cavity (coelom), and have bilateral symmetry, meaning their body can be divided into two equal halves along one plane.

Hemichordata was earlier considered as a sub-phylum under phylum Chordata. But now it is placed as a separate phylum under non-chordata. Hemichordates have a rudimentary structure in the collar region called stomochord, a structure similar to notochord.

Column IP. Notochord and hollow nerve cord present→ These are defining features ofPhylum Chordata.✅ So,P → iv (Chordata)Q. Ectoparasite with 6–15 pairs of gills and closed circulation→ Ectoparasitic, jawless vertebrates with multiple gill pairs and closed circulation areCyclostomes(e.g. lamprey).✅ So,Q → i (Cyclostomata)R. Marine animals with persistent notochord and placoid scales→ These features are typical ofcartilaginous fishes (Chondrichthyes)—like sharks, skates, and rays—where notochord persists and placoid scales are present.✅ So,R → ii (Chondrichthyes)S. Animals with open circulatory systems, and stomochord→ Stomochord and open circulation characterizeHemichordata(acorn worms).✅ So,S → iii (Hemichordata)Therefore, the correct matching is ✅Option Ais correct.