The biggest taxonomic rank is Kingdom. The next higher rank within a kingdom is the Phylum or Division. It is customary to use the term phylum for major groups in the animal kingdom and the term division for major groups in the plant kingdom. The phylum or division is a broad grouping of more or less closely related organisms, sharing certain common characteristics.
Each phylum or division has the next taxon called Class. The members of each class exhibit certain distinguishing characters that are unique only to them.
In the same way, using comparable criteria of similarities and relationships, each class can be divided into orders, each order into families, each family into genera and each genus into species. Species is normally the basic or fundamental unit of classification. A species is, therefore, the narrowest taxonomic category and kingdom is the broadest category in the Linnaean hierarchy.
Therefore, the correct answer is option C.