The maximum amount of energy that we should expect to be recycled from fox trophic level back to the grass trophic level is 0 units.
A food chain describes who eats whom in the wild. Every living thing – from unicellular algae to giant blue whales – needs food to survive. Every food chain is a possible pathway that energy and nutrients can travel through an ecosystem. The primary productivity of the grass is 200 units. There is a 10 fold decrease in the amount of energy units as we move upwards in production chain. So from grass to rabbits we lose energy. The foxes will only really have two units once it's decreased by 10 fold again. The grass does not get any energy from the decaying bodies of foxes, they get the minerals that they need to grow. And so the correct answer to this question is 0 units because when the energy gets recycled from fox trophic level back to the grass trophic level it will be totally reduced.
Note: The question seems to be incomplete. So the complete question is "Consider a hypothetical food chain consisting of grass, rabbits, and foxes. The primary productivity of the grass is 200 units. What is the maximum amount of energy that we should expect to be recycled from the fox trophic level back to the grass trophic level? Answer choices: A) 0 units B) 0.2 units C) 2 units D) 20 units"
