Which best describes the relationship between two species and a niche?

A niche is the role a species plays in its ecosystem, including how it uses resources. If two species occupy the same niche in the same habitat, they compete for the same resources, and they cannot stably coexist there indefinitely. This is why “Two species cannot occupy the same niche in the same habitat” is the best description; the outcome is not always extinction or movement, since species may instead use different resources or habitats.

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