AP EAMCET Medical 23 Apr 2019 Shift 2 Paper

Study the following statements
I) Digestion in sponges is extra cellular
II) Primary function of flame cells in flatworms is osmoregulation
III) Clitellum is absent in unisexual annelids
IV) Dipleurula larva is considered as the ancestor of echinoderms
Among the above, correct statements are