* Food web: A food web is a complex network of interconnected food chains within an ecosystem. It shows how different organisms feed on each other, depicting the flow of energy and nutrients.

Let's look at why the other options are incorrect:

* Trophic: Trophic refers to the feeding levels in an ecosystem. It's a broader term related to the food web but doesn't specifically describe the feeding relationships themselves.

* Biomass: Biomass refers to the total mass of living organisms in a given area or volume. It's not directly related to feeding relationships.

* Symbiosis: Symbiosis is a close and often long-term interaction between two different species. While some symbiotic relationships involve feeding, it's not the primary definition.

* Niche: A niche describes the role an organism plays in an ecosystem, including its food sources, habitat, and interactions with other organisms. While it incorporates feeding relationships, it's a broader concept.