Answer: A) Producers B) Consumers constitute the upper trophic levels. Unlike producers, they cannot make their own food. To get energy, they eat plants or other animals, while some eat both. c) Through the photosynthesis process, producers, such as grass, absorb the sun's light energy to produce food (stored sugar and starches). Consumers cannot make their own food, so they have to consume other organisms. The food of almost any kind of animal can be traced back to plants and the sun.