Identify the animal and plant groups having:
$(a)$ Animals without tissues,body bearing pores.
$(b)$ Plant body differentiated into roots,stems and leaves but do not produce seeds.
$(c)$ Body dorsoventrally flattened without coelom.
$(d)$ Segmented worms with true body cavity with extensive organ differentiation.

• A
  Porifera,Pteridophyta,Platyhelminthes,Annelida
• B
  Cnidaria,Bryophyta,Nematoda,Arthropoda
• C
  Ctenophora,Thallophyta,Annelida,Mollusca
• D
  Echinodermata,Gymnosperms,Platyhelminthes,Chordata