Concept:The largest population that an environment can support for a long time is known as its carrying capacity.Explanation:Every environment provides limited resources such as food, water, shelter, and space.Because these resources are limited, only a certain maximum number of individuals can survive in that environment over an extended period.This natural limit is determined by the environment's carrying capacity.When the population rises above this limit, resources become insufficient and the population may decline.Answer:D. carrying capacity