What is the primary function of decomposers in an ecosystem? a. decomposers are parasites; they attach themselves to host organisms and absorb nutrients from the host until the host organism dies. b. decomposers break down matter from dead organisms into simpler substances that can be recycled in ecosystems. c. decomposers absorb energy from the sun and produce food for themselves as well as other organisms. d. decomposers combine elements, such as carbon, nitrogen, and oxygen, into complex molecules that can be used as food sources for organisms.