An animal is described as triploblastic, bilaterally symmetrical, coelomate and metamerically segmented. It most likely belongs to phylum
APlatyhelminthes
BAnnelida
CAschelminthes
DCoelenterata
Answer & Solution
Correct answer: B. Annelida
1. Triploblastic + bilateral symmetry rules out Coelenterata (which is diploblastic + radial).
2. Being coelomate rules out Platyhelminthes (acoelomate) and Aschelminthes (pseudocoelomate).
3. Metameric segmentation is diagnostic of Annelida.
4. So the described animal fits Annelida (e.g., Pheretima, Nereis).
_Source: syllabus Biology, Ch 4 "Animal Kingdom", §4.2.6_
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