Which statement is MOST false about steel and wrought iron pipe?

The statement that they are always galvanized for corrosion resistance is the most inaccurate. While many steel pipes are galvanized to provide enhanced corrosion resistance, especially when used in outdoor or potentially damp environments, not all steel or wrought iron pipes are galvanized. There are applications and types of pipes where galvanization is not applied, depending on the specific use case or the internal environment of the application. For example, black iron pipes, which are commonly used for gas lines, are not galvanized but instead rely on other methods for protection from corrosion or are coated after installation.

The other statements have more validity; steel and wrought iron pipes indeed come in various shapes and sizes to accommodate diverse plumbing needs. They are also typically available in multiple weights, allowing for different structural applications. Additionally, these types of pipes are widely used in various plumbing applications, featuring prominently in both residential and commercial plumbing systems. Thus, stating that they are always galvanized does not hold true in all instances, making it the most false of the presented statements.