The correct description of the difference between a food chain and a food web is:
A food chain represents one possible pathway that energy and matter can take in an ecosystem. A food web contains multiple, interconnected food chains.
A food chain illustrates a linear sequence of who eats whom in an ecosystem, showing a single pathway of energy flow from producers to various levels of consumers. In contrast, a food web is a more complex representation that depicts multiple interconnected food chains, demonstrating how various organisms are related through multiple feeding relationships within an ecosystem. This complexity allows for a more realistic representation of the interactions between different species.