What is the basic unit of classification?

How many of the following statements are correct?
$(A)$ Each taxonomic category is a unit of classification.
$(B)$ Taxonomic groups are distinct biological entities.
$(C)$ Genera are aggregates of closely related families.
$(D)$ Both vegetative and reproductive characters are used to characterise the families.

Which of the following represents the correct match of an animal with its taxonomic category?

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.

The only taxonomic category that has a real existence is...

What is the order of mango $(Mangifera \text{ } indica)$?