Question Detail
Question
Which phylum is unique for being asymmetrical and lacking true tissues/organs?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Under 'Phylum Porifera (Sponges)', it is described as 'Non-motile (sessile), multicellular, no true tissues/organs, outer skeleton (spicules/spongin)' and 'no symmetry (asymmetrical)'. The 'Quick Revision' table also lists 'Filter feeders; asymmetrical' as a unique fact.
Hint
These are the simplest multicellular animals.