Ponds and rivers are two types of . . . . freshwater ecosystems
Freshwater ecosystems, because marine includes things more like the ocean depths, rain forests are FORESTS, and rivers and ponds have fresh water.
The answer to the question is option C: freshwater ecosystems. Ponds and rivers are both types of freshwater ecosystems, characterized by low salt concentrations and supporting a variety of plant and animal life. They are essential for providing resources such as drinking water and habitats for wildlife.
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