Which color identifies a ball round?

• A. Full black
• B. No color
• C. Blue stripe
• D. Black tip

Answer: (B)

Roundness is a geometric property, not a color property. A ball is defined by its spherical shape—the same curvature all around—so color or markings don’t determine that it’s round. Any color, stripe, or tip could appear on many different objects and doesn’t uniquely identify a ball’s round shape. The only option that avoids introducing a color cue and relies on shape alone is no color, making it the best choice.