What type of organisms are consumers classified as?

Consumers are defined as organisms that rely on other organisms for energy, which is precisely what option C states. They obtain their nutrients by consuming other living things, whether they are plants, animals, or microorganisms. This group includes a variety of organisms such as herbivores, carnivores, and omnivores, which play essential roles in food webs by transferring energy from producers to higher trophic levels.

In contrast, the other options describe different types of organisms and biological processes. Organisms that make their own food, such as plants and some algae, are classified as producers. Those that decompose organic material include fungi and certain bacteria, which recycle nutrients back into the ecosystem, and this function is crucial for maintaining soil health and fertility. Meanwhile, organisms that fix carbon from the atmosphere, primarily plants through photosynthesis, are also producers rather than consumers. Understanding these classifications is fundamental in ecology, as it helps illustrate the flow of energy within an ecosystem.