Which materials are commonly used for water pipes?

The choice of PVC, ductile iron, and cast iron reflects the common materials used in water distribution systems due to their favorable properties for handling pressurized water transport.

PVC, or polyvinyl chloride, is widely used for its lightweight, corrosion resistance, and ease of installation. It is particularly effective in various applications, including potable water supply and drainage systems.

Ductile iron is known for its strength and durability, making it suitable for high-pressure applications. Its ability to withstand heavy loads and resist corrosion when properly coated adds to its reliability in long-term water distribution systems.

Cast iron has been used for many years in water pipes due to its strength and longevity. While it is heavier and more brittle than ductile iron, it still finds use in many older systems and in certain modern applications.

This combination of materials in option B provides a practical solution for modern water distribution, ensuring that systems are both efficient and durable. Other materials listed in the other choices do not typically meet the same performance standards for water piping, which limits their application in this context.