Animals like tigers,cats,and dogs are included in the order ....

Which taxonomic category covers the largest number of organisms?

What is the term given to the groups of organisms arranged at different levels of classification?

Select the correct statements $(i-iv)$ regarding taxonomic categories.
$(i)$ Each step or rank in hierarchy is called taxonomic category.
$(ii)$ Species is a group of individual organisms with fundamental similarities capable of breeding among themselves.
$(iii)$ Taxonomic studies of all unknown organisms have led to the development of common categories like kingdom,phylum or division,class,order,family,genus and species.
$(iv)$ Lower the category,greater is the difficulty of determining the relationship to other taxa at the same level.

Which of the following statements are not correct?
$(i)$ Lower the taxon,more are the characteristics that the members within the taxon share.
$(ii)$ Order is the assemblage of genera which exhibit a few similar characters.
$(iii)$ $Cat$ and $dog$ are included in the same family Felidae.
$(iv)$ Binomial nomenclature was introduced by Carolus Linnaeus.

In the given diagram,what do the parts labeled $P$ and $Q$ represent respectively?