Question

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Explanation:

In the context of natural habitats and erosion, the missing word should relate to the environmental conditions that flora and fauna rely on. "Soil" is a key component of habitats affected by erosion, as stable soil conditions are crucial for plant growth (flora) and the organisms (fauna) that depend on those plants or the soil ecosystem. Erosion degrades soil, so "soil" fits here to describe the stable conditions flora and fauna need.

Answer:

soil