Rice,cereals,monocots and plants represent

Who published the book 'Species Plantarum' and provided a basis for the classification of plants?

Four statements are given below regarding the nomenclature of organisms. Which two statements are correct?
$(1)$ The first name denotes the species and the second denotes the genus.
$(2)$ $A$ species name used for one organism cannot be used for another organism.
$(3)$ Each word in a handwritten scientific name must be underlined.
$(4)$ It is mandatory to write the sub-species name after the species name for every organism.

Which of the following represents the correct ascending order of taxonomic categories based on the number of organisms?

In the binomial nomenclature of an organism,whose name is written in an abbreviated form after the specific epithet?

The basic unit of classification / taxonomy is