The appearance of color for an object can change primarily due to which factor?

• A. Available light
• B. Object's pigment
• C. Shape of object
• D. Viewing distance

Answer: (A)

Color that we perceive is determined by the light that illuminates the object. The light’s spectrum and quality dictate which wavelengths reach our eyes after interacting with the object’s surface or material. Different light sources have different spectral content—daylight is broad, incandescent lighting skews toward red/yellow, and fluorescent lighting has spikes in certain wavelengths—so the same object can look different under each one. The pigment or material decides which wavelengths are reflected or transmitted, but it’s the available light that mainly shapes the observed color. The shape or distance can affect brightness or saturation through shading or perspective, but they don’t drive the fundamental color change like illumination does.