Final answer:
Primary treatment includes methods like Activated Sludge Process and Oxidation Ponds. Trickling Filter is an example of a secondary treatment method. No example is given for tertiary treatment.
Step-by-step explanation:
Primary treatment is the first phase of wastewater treatment, where solids and oil are separated from the wastewater. Examples of primary treatment methods include Activated Sludge Process and Oxidation Ponds. Secondary treatment is the second phase, which involves the breakdown of organic matter by microorganisms. The Trickling Filter is an example of a secondary treatment method. Tertiary treatment is the final phase and is used to further clean the water before it is discharged into a sensitive ecosystem. Tertiary treatment is not mentioned in the provided information, so we cannot identify an example for this category.