Which one of the following is a species?

Which of the following statements is correct regarding a species?

Identify the correct terms for the following statements:
$(i)$ The science of classifying all organisms into different taxa based on their characteristics.
$(ii)$ The system of naming organisms following specific rules.
$(iii)$ The branch of science that includes the study from populations to the biosphere.
$(iv)$ The structure formed by the combination of all taxonomic categories.

Which of the following options indicates a decrease in variations?

Rice and brinjal belong to the category ending with the suffix:

Give an example of a taxonomic category hierarchy.