Which quality is lacking when something is described as drab?

• A. Brightness
• B. Color
• C. Luster
• D. Gloss

Answer: (C)

This item tests understanding of how light interacts with a surface and how that shows up in everyday adjectives. Drab describes something dull and lifeless, lacking the kind of gleam that catches the eye. Luster is the quality of a surface’s sheen or glow—the way it reflects light. When something is described as drab, that reflective shine is missing, so it lacks luster. Brightness is more about how much light is emitted or reflected, which can exist without a shiny finish. Color refers to the hue, which can be dull even if there’s a bit of gloss. Gloss denotes a shiny, polished finish, a specific kind of shine, but drab centers on the overall lack of that gleam, i.e., luster.