Answer:
Food chain is defined as the linear network that shows the energy flow between different levels of ecosystem.
Each food chain starts with energy from sun. the next step is plants (producer) utilise the sunlight and make their own food. Other animals or insects feeding plants are called consumer. The insects feed over plants (primary consumer) and then insects wil be cnsumed by birds (secondary consumer).
Hence, the food chain that includes insect-eating birds is:
Solar energy => Plants (producers) => Insects (primary consumer) => Birds (secondary consumer)