The correct answer is "a. genus." The genus name is always written first in a scientific name. A scientific name consists of two parts: the genus name and the species name. These two names together make up the scientific name of a particular organism. The genus name represents a broader group or category, while the species name represents a specific organism within that genus. For example, in the scientific name for humans, Homo sapiens, "" is the genus name and "sapiens" is the species name.
