Which statement about aluminum finishes is true?

• A. Hydroxide
• B. Patina
• C. Alloy
• D. Oxide

Answer: (D)

Aluminum finishes revolve around an oxide layer. When aluminum meets air, it quickly forms a thin, protective oxide film that gives corrosion resistance and a clean surface. This oxide layer can be made thicker through anodizing, which not only enhances protection but also allows for color and improved wear resistance. So describing an oxide finish is correct because it highlights the natural and common surface protection of aluminum. The other terms don’t fit as finishes: hydroxide isn’t the typical protective coating used on aluminum, patina is more associated with copper alloys, and alloy refers to composition, not a surface finish.