The number of different species accounts for SPECIES DIVERSITY. The term biodiversity is a more complex term that should include not only the number of species diversity, but the genetic diversity and the ecosystem diversity of that area.
The chromosome theory of inheritance, or the idea that genes are located on chromosomes, was proposed based on experiments by Thomas Hunt Morgan using Drosophila melanogaster, or fruit flies.
A mountain lion population recently experienced a drop in population size. The best limiting factor that is involved is- The deer population experienced a rapid decline due to a parasite.
Only this could be the best possible answer out of all other options because when there are no deer, there is no food for the lions.