The correct option is B Porifera and Annelida - Phyla
Oligochaeta is a subclass of phylum Annelida, while Arthropoda is a phylum.
Hydrozoa is a class but Mollusca is a phylum.
Aves is a class of Chordata phylum.
Porifera and Annelida both are phyla of animal kingdom. Thus, the correct answer is option B.