Electromagnetic spectrum regions relative to visible light

Steps:

• Wavelength and frequency are inversely related by c = fλ, so longer wavelength means lower frequency.
• Visible light spans 400-700 nm wavelengths.
• Infrared region has wavelengths >700 nm, longer than visible.
• Ultraviolet region has wavelengths <400 nm, shorter than visible, thus higher frequency.

Why A is correct:

• Infrared has longer wavelength than visible light (700 nm to 1 mm), and ultraviolet has higher frequency (shorter wavelengths 10-400 nm), per c = fλ.

Why the others are wrong:

• B: Microwave and radio both have longer wavelengths (>1 mm) and lower frequencies than visible.
• C: Ultraviolet has higher frequency but shorter wavelength; microwave has longer wavelength but lower frequency.
• D: Ultraviolet has higher frequency but shorter wavelength; infrared has longer wavelength but lower frequency.

Final answer: A