A.Incoming water current and are located in the body wall of sponges
B.Excretory products and are located inside the body of flat-worms
C.Outgoing water current and are located on the top of sponge
D.None of these
A.Incoming water current and are located in the body wall of sponges
B.Excretory products and are located inside the body of flat-worms
C.Outgoing water current and are located on the top of sponge
D.None of these