Which of the following is not an aquatic animal?

State the type of body cavity found in Platyhelminthes. Write whether they are parasitic or free-living.

Differentiate between the following:
$(a)$ Tube system of feather star and canal system of $Euplectella$
$(b)$ Skeleton of shark and sea horse
$(c)$ Respiratory organs of tadpole and frog
$(d)$ Forelimbs of birds and lizard
$(e)$ Skin of tree frog and human

Give reasons for the following:
$(i)$ Bryophytes are called amphibians of the plant kingdom.
$(ii)$ From phylum Platyhelminthes onwards,animals are categorized as 'triploblastic.'
$(iii)$ The presence of 'coelom' in an animal's body is considered advantageous.

Which organism is more complex and evolved among Bacteria,Mushroom,and Mango tree? Give reasons.

Explain how,'Two areas of study namely $evolution$ and $classification$ are interlinked'. Justify this statement.