Final answer:
The binomial name of the American toad should be written as Bufo americanus, following the rules of binomial nomenclature.
Step-by-step explanation:
The binomial name for the American toad, adhering to binomial nomenclature conventions, is correctly expressed as Bufo americanus. In this system, the genus name (Bufo) is capitalized, the species name (americanus) is in lowercase, and both are italicized when printed. Binomial nomenclature, devised by Carl Linnaeus, provides a standardized way of naming and categorizing species, ensuring clarity and consistency in biological communication. This systematic approach aids scientists in accurately identifying and classifying organisms, fostering a universal understanding of biodiversity. Hence, the name Bufo americanus precisely denotes the American toad within the context of biological taxonomy.