What describes the process of breaking down organic material into gases and inert substances by bacteria?

The correct answer is stabilization. This term refers specifically to the process where organic material, such as sewage and other biodegradable waste, is broken down by microbial activity into simpler substances, primarily gases like methane and carbon dioxide, along with inert materials. Stabilization is a vital aspect of wastewater treatment, as it reduces the volume of sludge and transforms potentially harmful organic compounds into less toxic forms.

In wastewater treatment, stabilization typically occurs during primary and secondary treatment phases, where bacteria metabolize the organic matter. In the process, these bacteria not only stabilize the waste by reducing its biochemical oxygen demand but also produce gases that can be captured and utilized as energy.

Decomposition also involves the breakdown of organic matter by microorganisms, but it is a broader term that encompasses various scenarios outside the specific context of wastewater treatment. Disinfection and filtration are methods used to remove pathogens and particles, respectively, but they do not involve the biological breakdown of organic material as a primary function.