Answer: Sun →hay→ rabbit→ eagle.
Step-by-step explanation: The food chain can be defined as the flow of energy in the ecosystem in a correct order. The flow of the energy in the ecosystem starts from the producers.
Here, the sunlight is used by the hay ( producer) of the ecosystem to make food by the help of the process known as photosynthesis.
Then it is eaten by the rabbit( primary consumers) which is then consumed by eagle ( secondary consumers).