In ________ environment the sediment characteristics often detemine the type of benthic animals.

Explanation

**Step-by-Step Solution:**

1. **Understanding Benthic Animals**: Benthic animals are organisms that live in the benthic zone, which is the lowest layer of a body of water, including oceans, rivers, and lakes. They are found at the bottom of these water bodies.

2. **Characteristics of the Benthic Zone**: The benthic zone is characterized by the absence of sunlight, which affects the types of organisms that can thrive there. Since sunlight does not penetrate this zone, photosynthetic organisms are limited.

3. **Food Sources for Benthic Animals**: Benthic animals primarily obtain their food from organic matter that settles to the bottom, such as algae and organic runoff from land. This reliance on organic material influences their distribution and diversity.

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