Biodiversity is the total of the genetic varieties of all organisms in the biosphere, including diversity within species, between species, and across ecosystems, option C is correct.
The total of the genetic varieties of all organisms in a biosphere is referred to as biodiversity. Biodiversity encompasses not only species diversity, which is the variety of different species but also genetic diversity within those species, as well as the diversity of ecosystems. This concept is critical because it reflects the full range of life's variation, from the genetic level to the complex interactions within ecosystems, option C is correct.