Final answer:
In binomial nomenclature, both the genus and species names are italicized, with the genus name capitalized and the species name in lowercase. Therefore, the correct option is A.
Step-by-step explanation:
Binomial nomenclature is a system used for naming organisms scientifically. When using binomial nomenclature, the proper formatting is to italicize both parts of the name. Therefore, both the genus and species names are italicized. Specifically, the genus name is capitalized, and the species name is not. This creates a universal scientific name for each organism that can be recognized worldwide, avoiding confusion over regional names. An example of binomial nomenclature is the scientific name for humans, Homo sapiens, where 'Homo' is the genus and 'sapiens' is the species.