Final answer:
In the food chain grass → grasshopper → snake → hawk, the heterotrophs are the grasshopper, snake, and hawk. These organisms feed on other organisms to obtain energy as they cannot produce their own food. Grass, being an autotroph creates its own food and is food for others.
Step-by-step explanation:
In the given food chain (grass → grasshopper → snake → hawk), the heterotrophs are represented by option D, which includes the grasshopper, snake, and hawk. Heterotrophs are organisms that must obtain energy and carbon from food by consuming other organisms. The grasshopper, snake, and hawk all satisfy this criteria, as they feed on other organisms and do not have the ability to produce their own food through processes like photosynthesis.
On the contrary, grass, represented here as the base of the food chain, is considered an autotroph because it creates its own food via photosynthesis, converting sunlight into chemical energy. These autotrophs serve as the primary source of food and energy for heterotrophs in an ecosystem, making them essential for the survival of heterotroph organisms.
Learn more about Heterotrophs