Which color has a higher frequency among red, blue, green, yellow?

• A. Red
• B. Green
• C. Yellow
• D. Blue

Answer: (D)

Light frequency is higher when the wavelength is shorter. In the visible range, red has the longest wavelength (about 700 nm), which means the lowest frequency among these colors. Blue light has a shorter wavelength (around 450 nm), so its frequency is higher than red, green, and yellow. Green and yellow have even longer wavelengths than blue, so their frequencies are lower. Because shorter wavelengths correspond to higher frequencies, blue is the color with the highest frequency among red, green, yellow, and blue.