Final answer:
The subject of this question is Biology, and it is at a High School grade level. The answer explains the term heterotroph and provides definitions and examples of decomposer, consumer, and parasite. The correct answer to the question is 'Consumer' as heterotrophs obtain energy by consuming other organisms.
Step-by-step explanation:
All heterotrophs are organisms that rely on consuming other organisms for their energy needs. They cannot produce their own food and depend on external sources. The given options are:
a) Decomposer: Decomposers are organisms that break down dead organic matter and recycle nutrients back into the environment. They obtain energy by digesting and absorbing nutrients from decaying material.
b) Consumer: Consumers are organisms that obtain energy by consuming other living organisms. They can be further categorized into different trophic levels based on their feeding habits.
c) Parasite: Parasites are organisms that live on or inside another organism (host) and derive their nutrition from the host. They harm the host but do not typically kill it.
Therefore, the correct answer to the question is Consumer.
Learn more about Heterotrophs