Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: An ecosystem is a community of organisms interacting with their physical environment. Why are decomposers an important part of ecosystems?
They break down dead organisms to return nutrients to the soil.
Decomposers break down dead organisms, recycling nutrients back into the ecosystem.