What defines the carrying capacity of an environment?

The carrying capacity of an environment is defined as the maximum number of individuals of a particular species that an ecosystem can sustainably support over time without leading to degradation of the environment. This concept encompasses various factors, including the availability of food, water, shelter, and other essential resources. When a population exceeds its carrying capacity, the environment may become overstrained, which can lead to resource depletion and ultimately a decline in the population due to competition, starvation, disease, or emigration.

While the availability of resources is related to carrying capacity, it is not the only defining factor. Lifespan of individuals and the number of species present do not directly determine how many individuals of a species the environment can sustain. Therefore, the correct answer focuses directly on the idea of maximum population support within the limits of the environment.