Answer:
C. Park rangers plant a new type of tree.
Explanation:
Biodiversity is a term used to describe the "variety" of plants and animals within the given ecosystem. To offset the current biodiversity, a species must be introduced or taken away. In this case, a "new type of tree" is introduced into the ecosystem, which would affect the ecosystem based on the land availability to native species, as well as what kind of things (diseases, etc) it brings to the ecosystem. If the species take over, animals must adapt to be able to live with the new plant.
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