Which types of bacteria are commonly used in wastewater treatment?

In wastewater treatment, various types of bacteria play crucial roles in the decomposition of organic matter and the removal of pollutants. The correct answer highlights the significance of aerobic, anaerobic, and facultative bacteria.

Aerobic bacteria thrive in the presence of oxygen, utilizing it to break down organic materials effectively in processes like activated sludge treatment. Anaerobic bacteria, on the other hand, can operate without oxygen and are essential in processes such as anaerobic digestion where they help in stabilizing waste and producing biogas. Facultative bacteria have the ability to switch between aerobic and anaerobic metabolism based on the availability of oxygen, making them versatile and crucial in various treatment situations.

These groups of bacteria work together to ensure efficient treatment of wastewater, making them indispensable for a functioning sewage treatment system. Other options, while they contain types of bacteria relevant to specific processes, do not encompass the full range necessary for comprehensive wastewater treatment operations.