What does "biodiversity" refer to?

Biodiversity encompasses the variety of life forms within a given habitat, ecosystem, or on Earth as a whole. This includes the diversity of species, genetic variations, and the complex ecosystems formed by these species interacting with each other and their environment. When discussing biodiversity, it is crucial to understand that it is not limited to just the number of species, but rather includes the richness and variety of these species, as well as the various ecosystems they inhabit and the interactions among them.

The first choice captures this broad concept well by highlighting the variety of life in a particular habitat or ecosystem, which is essential for ecological balance and resilience. Diverse ecosystems tend to be more productive and can better withstand environmental stressors, making this definition central to understanding the importance of biodiversity in conservation and environmental management.

While the other options touch on components of biodiversity—such as species richness or genetic diversity—their scope is narrower. The second choice focuses specifically on the number of species, lacking the inclusion of ecosystem interactions and community dynamics. The third choice addresses the health of a specific population, which is only one aspect of biodiversity and does not represent the overall variety of life. The last choice pertains to genetic diversity within a single species, an important point in terms of adaptability and resilience,