Which of the following is absent in the sub-category 'Order'?

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.

Each step of classification represents a:

Which of the following taxonomic categories contains organisms with the least number of similarities?

Which of the following is a universal rule of nomenclature?

How are scientific names of plants and animals assigned?