Which process is best described as a natural mechanism that leads to the evolution of organisms best suited to their environment?

Natural selection is the process that leads to the evolution of organisms that are best suited to their environment. This mechanism operates on the principle that individuals within a species exhibit variation in their traits, some of which may confer advantages that enhance survival and reproductive success in a given environment. Those individuals with advantageous traits are more likely to survive, reproduce, and pass on their traits to the next generation. Over time, this leads to a population that is better adapted to its environment.

In contrast, carrying capacity refers to the maximum number of individuals of a particular species that an ecosystem can support sustainably. While it influences population dynamics, it does not directly explain how specific adaptations arise.

Adaptive radiation describes a process in which a species evolves rapidly into a variety of forms to adapt to different environments, but it is not specifically the natural mechanism of selection itself.

Limiting factors are environmental conditions that restrict the growth, abundance, or distribution of an organism within an ecosystem. While they play a role in the survival of organisms, they do not explain the specific evolutionary process that allows for adaptation through selected traits. Therefore, natural selection stands out as the primary process by which evolution occurs in response to environmental pressures.