Red Seal Plumbing Practice Exam 2025 - Free Red Seal Plumbing Practice Questions and Study Guide

Electrolysis occurs when two dissimilar metals come into contact, resulting in a chemical reaction. This question asks specifically about the damaging force of electrolysis, and which combination of metals would most likely cause this reaction. All the choices provided are incorrect except for C, which states "Ferrous metals and non ferrous metals." The other options list specific metals, while C is referring to general categories of metals. Iron and copper may be individually susceptible to electrolysis, but this question is exploring the damaging force of two types of metals that are inherently different. Similarly, the combination of copper and aluminum may also result in electrolysis, but this is not the only possible combination that would cause this reaction. Choice D is also incorrect because it lists two specific metals instead of general categories. Thus, C is the most accurate and comprehensive answer to this question.