Since this is movement that is occurring against the natural movement from high to low concentration, this is Active transport.
The option C.
Reading background information because it gives ideas from the author himself.
Answer:
The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat.
Explanation:
