Which of the following is true concerning energy flow through an ecosystem's food chain? a. Primary consumers collect their energy from the sun. b. The sun is the final receiver of energy in an ecosystem. c. Energy is lost at each successive energy level in the chain. d. Tertiary consumers account for the largest store of energy.

The main source of energy in a food chain is the sun. In each link of the food chain, energy is transferred which means, the last consumer has the least energy uptake. The producers obtained a lot of energy from the sun, the primary consumers too collect more energy compared to the secondary to the last consumer of the food chain. Thus, the answer to this item is letter c. Energy is lost at each successive energy level in the chain.