Which animal possesses choanocytes?

Animals devoid of respiratory,excretory,and circulatory organs belong to the phylum:

In animals of the phylum Porifera,through which structure does excess water exit the body?

Which phylum is characterized by a body with an internal cavity lined by food-filtering flagellated cells (choanocytes) and indirect development?

Which one of the following statements about all the four of $Spongilla$,leech,dolphin and penguin is correct?

Assertion $(A):$ The body of sponges is supported by a skeleton.
Reason $(R):$ The skeleton of sponges is made up of spicules and spongin fibres.