Which of the following pipe materials is least likely to corrode?

PVC, or polyvinyl chloride, is a type of plastic commonly used in plumbing applications. One of its key advantages is its exceptional resistance to corrosion. Unlike metal pipes, which can deteriorate over time due to exposure to moisture, chemicals, and various environmental factors, PVC is impervious to these issues. This characteristic makes PVC an ideal choice for a wide range of plumbing systems, especially in areas with aggressive water conditions or where exposure to corrosive substances is likely.

In contrast, copper can corrode due to oxidation and reaction with water or other elements, especially in acidic conditions. Cast iron is prone to rusting and corrosion when it comes into contact with moisture and air, which can lead to structural weaknesses over time. Galvanized steel, although coated to prevent rusting initially, can also suffer from corrosion underneath the zinc layer once it wears off. Given these properties, PVC stands out as the most corrosion-resistant material among the options provided.