Which of the following best describes competitive exclusion?

Competitive exclusion refers to the principle that two species competing for the same limited resource cannot coexist at constant population values. When two species vie for the same niche and resources, one species will invariably outperform the other, leading to the complete exclusion or extinction of the weaker competitor. This concept is fundamental in ecology as it highlights the consequences of competition on biodiversity and species distribution.

In the context of the options provided, one species completely outcompeting another is the essence of competitive exclusion. This outcome arises in environments where resources such as food, space, or other essentials are scarce, and the superior competitor will dominate and monopolize these resources. The result is that the less competitive species either adapts to a different ecological niche or declines in population until it can no longer sustain itself.

The other options describe different ecological interactions or dynamics. For instance, two species thriving together suggests a form of mutualism or coexistence that does not align with the principle of competitive exclusion, where coexistence is not possible under the same conditions. Similarly, species evolving to avoid competition hints at niche differentiation instead of outright exclusion, as they may adapt to different resources or habitats rather than directly outcompeting one another. Lastly, species benefiting from sharing resources refers to a form of facilitation or