Which are smaller than many protists but are truly multicellular and have specialized organ system?

جو بہت سے پروٹسٹوں سے چھوٹے ہیں لیکن واقعی کثیر خلوی ہیں اور ان میں مخصوص اعضاء کا نظام ہے؟

Rotifers

Jellyfish

Branchiopods

None of these

Rotifers are microscopic, multicellular organisms with specialized organ systems, including a complete digestive tract.

They are smaller than many protists but exhibit complex biological structures.