Given organisms belong to how many genera?

Wheat,Brinjal,Potato,Lion,Dog,Tiger

Which of the following is a universal rule of nomenclature?

Which of the following shows the correct example of the taxonomic category - Genus?

$Leo$ and $nigrum$ are respectively .......

Which of the following represents the order of a horse?

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.