What constitutes sufficient color contrast for readability?

• A. Sufficient contrast between foreground text and its background
• B. Using black text on white background only
• C. Any color combination is acceptable
• D. Increasing font weight only

Answer: (A)

Readable text depends on enough color contrast between the foreground and its background. When the text color and the background differ in luminance by a sufficient amount, the characters stand out clearly and are easier to read under typical viewing conditions.

Guidelines quantify this with a contrast ratio. For normal-sized text, aim for at least a 4.5:1 ratio; for larger text, 3:1 can be acceptable. The exact colors can vary—black on white is a common example that usually meets the standard—but the important idea is the measured contrast, not a specific color pair.

Increasing font weight alone doesn’t fix poor contrast. Even bold text can be hard to read if the contrast ratio is too low. Likewise, some color combinations with low luminance difference will fail the test even if they look acceptable at a glance.