Question :
Which of the following is correctly sequenced?
  a) Phylum, class, order, family b) Phylum, order, class, genus
  c) Phylum, class, family, order d) Phylum, order, family, class

Answer :
(a) The system by which various taxonomic categories are arranged in a proper descending order is called taxonomic or systematic hierarchy. The correct sequence of categories in systematic hierarchy is- Kingdom, sub-kingdom, division or phylum, class, sub-class, series, order, family, genus, species.