For which class of organisms did Linnaeus officially apply his nomenclature system in 1753?

Correct answer: For plants

Correct answer: A, plants. Linnaeus’s 1753 work Species Plantarum is conventionally treated as the starting point for the accepted scientific naming of plants under modern botanical nomenclature. A scientific name gives an organism a standard name that can be used internationally instead of relying on different local names. Option A is correct because the 1753 publication dealt with plant species. Option B is incorrect because Linnaeus’s major work on animals, Systema Naturae, was published in an earlier edition in 1758, not 1753. Option C is incorrect because bacterial naming was developed much later. Option D is incorrect because fungi are now treated under botanical nomenclature, but the specific 1753 milestone refers to plants. Memory cue: “1753—Species Plantarum—plants; 1758—animals.”