Warning signs have what color scheme?
Answer: C — Yellow with Black letters
Warning signs typically have a yellow background with black letters. This color scheme is easily visible and draws attention to important warnings and hazards ahead. Options A, B, and D do not follow the standard color scheme for warning signs and may cause confusion or make the sign less noticeable. Green and blue are often used for informational signs, while red is reserved for stop and prohibition signs. Therefore, C is the best option for warning signs.