Which of the following categories contains the most species?

a.) class
b.) genus
c.) order
d.) phylum

The correct answer among the choices presented is option D. Phylum contains the most species. In the taxonomic rank, the phylum is place third in the rankings. Next to it, is class, order, family, genus, species. Hope this answers your question.

the burning of fossil fuels releases carbon dioxide and other greenhouse gases.good luck! =)cutie~