Final answer:
The correct method for joining Polyethylene sewer pipe is welding, which creates a seamless and strong joint suitable for the material.
Step-by-step explanation:
An acceptable method for joining Polyethylene sewer pipe is welding. Polyethylene is a type of plastic that cannot be effectively joined by soldering, gluing, or bolting, as these methods are either ineffective or inappropriate for the material's properties.
Welding, specifically butt fusion welding or electrofusion welding, is used to create a seamless and strong joint, ensuring the integrity of the sewer line.