Classification of organisms as producers depends on their ability to make their own food through the process of photosynthesis. This process involves converting sunlight, water, and carbon dioxide into energy-rich molecules like glucose. By producing their own food, these organisms form the base of the food chain and are vital for the survival of other organisms in the ecosystem.
Examples of producers include plants, algae, and some types of bacteria. These organisms play a crucial role in ecosystems by capturing energy from the sun and converting it into a form that other organisms can consume. In contrast, consumers rely on consuming other organisms for their energy needs.
Therefore, the correct answer to the question is:
c. make their own food
