Answer the following question given this paragraph: 

Like bacteria, archaeans are important decomposers. For example, archaeans help break down sewage in waste treatment plants. As decomposers, they help recycle carbon and nitrogen.


Q: Archaeans help break down sewage in waste treatment plants, so they fulfill what important role?

 Choices:

- producers

- consumers

- pollenation

- decomposer

A:
decomposer
