Question

which of the three classes of phylum porifera has spicules made of calcium carbonate? class calcarea class diptera

Explanation:

Porifera phylum has three classes: Calcarea, Hexactinellida, and Demospongiae. Class Calcarea has spicules made of calcium carbonate. Class Diptera is not part of Porifera (it's an insect class in Arthropoda).

Answer:

Class Calcarea