The most likely amount of energy available to secondary consumers of this ecosystem is 150kcal (Option B).
- In a food chain, primary producers (e.g., plants) use energy from the sunlight to synthesize their own food in the form of simple carbohydrates (e.g. glucose).
- Subsequently, primary producers serve as the food of primary consumers (e.g., herbivores), which are then eaten by secondary consumers (e.g., carnivores) and so successively.
- Thus, the energy flows from one trophic level of the food chain to the next.
- Energy decreases at a rate of 90% at each trophic level because energy is primarly lost as metabolic heat.
- In this case, 150 kcal corresponds to 1% of the initial energy, which is expected as energy moves up two trophic levels.
In conclusion, in this case, the most likely amount of energy available to secondary consumers is 150kcal (Option B is correct).