Q. Which of the following is the correct food chain? Answer:
Phytoplankton - Zooplankton - Fish
Notes: The correct food chain is phytoplankton → zooplankton → fish. This food chain shows the flow of nutrients and energy from one organism to another at different trophic levels. In this food chain, phytoplankton are the producers, zooplankton are the primary consumers, and fish are the secondary consumers.