Which of the options is not a valid CSS color specification?

Which of the options is not a valid CSS color specification?

• A. #000000
• B. rgb(0,0,0)
• C. rgb(red, green, blue)
• D. named colors like blue

Answer: (C)

In CSS, colors can be defined using hex codes, rgb() with numeric channels, or named colors. The hex form (#000000) is valid, rgb(0,0,0) is valid, and a named color like blue is valid. The rgb form with color names inside it—rgb(red, green, blue)—is not valid because rgb() must take numeric values (0-255 or percentages) for each channel, not words. Since those are not numbers, the browser cannot interpret the color.

In CSS, colors can be defined using hex codes, rgb() with numeric channels, or named colors. The hex form (#000000) is valid, rgb(0,0,0) is valid, and a named color like blue is valid. The rgb form with color names inside it—rgb(red, green, blue)—is not valid because rgb() must take numeric values (0-255 or percentages) for each channel, not words. Since those are not numbers, the browser cannot interpret the color.