What does food chain show?

Explanation

### Step-by-Step Solution:

1. **Definition of Food Chain**: A food chain is a sequence that shows how energy and nutrients flow from one organism to another in an ecosystem. It illustrates the feeding relationships between different organisms.

2. **Interconnection of Organisms**: In a food chain, all living organisms are interconnected. This means that each organism plays a role in the ecosystem, either as a producer, consumer, or decomposer.

3. **Producers**: The first level in a food chain consists of producers, which are organisms that can make their own food. An example is green grass, which uses photosynthesis to produce energy.

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