Here's a problem to solve: In a food pyramid, which best explains why the number of organisms decreases from one trophic level to the next?

Among the 4 following options, which is the correct answer?

- A: Consumers at the lower level require more energy than the top-level consumers.
 
- B: Consumers at the top level require more energy than the lower-level consumers.
 
- C: The consumers are feeding on larger organisms that have less energy.
 
- D: The consumers are feeding on smaller organisms that have less energy.
 