Study the following statements carefully

i) Flame cells help primarily in osmoregulation in flatworms

ii) In flatworms with digestive system, gut is sac like with only Anterior aperture but not posterior aperture.

iii) Trematodes and Cestodes are exclusively parasitic flat worms.

In flatworms, flame cells help osmoregulation and excretion, primarily in osmoregulation.

In flatworms digestive system is absent in parasitic forms and in free forms digestive system is incomplete two way gut i.e. mouth is present, anus is absent.

Class Trematodes and Cestodes includes all parasitic flat worms.