The excretory organ of crustaceans is:

The green gland is its excretory organ.

Malpighian tubules are the excretory structures of

The excretory organ of flatworms/Taenia is .........

Match the excretory organs listed under column $I$ with the animals given under column $II$. Choose the answer which gives the correct combination of alphabets of the two columns.

Column $I$ (Excretory organs)	Column $II$ (Animals)
$A$. Nephridia	$p$. Hydra
$B$. Malpighian tubules	$q$. Leech
$C$. Protonephridia	$r$. Shark
$D$. Kidneys	$s$. Round worms,$t$. Cockroach

Which are the excretory organs in crustacean animals?