1. 8375. Of the following, when and/or where is galvanic corrosion is most likely to occur? A. When an electrolyte (water) covers the surface of an aluminum skin, seeps into the cracks between lap joints, and oxygen is excluded from the area B. At the interface of a steel fastener and aluminum alloy inspection plate in the presence of an electrolyte C. In an area of unprotected metal exposed to an atmosphere containing battery fumes, exhaust gases, or industrial contaminants.