Electromagnetic spectrum wavelength order

Steps:

• Recall the electromagnetic spectrum order by increasing wavelength: gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, radio waves.
• Identify sequences that follow this progression from shortest to longest wavelength.
• Check each option for correct directional order without skips in the spectrum.
• Select the option with consecutive waves in increasing wavelength.

Why D is correct:

• Gamma rays, X-rays, and ultraviolet are consecutive in the spectrum with wavelengths increasing from <0.01 nm to 10 nm to 400 nm, per the standard EM spectrum classification.

Why the others are wrong:

• A: Sequence goes from longest (radio waves) to shortest wavelength (gamma rays), reversing the order.
• B: Sequence decreases wavelength from visible light (400–700 nm) through ultraviolet to X-rays.
• C: Skips ultraviolet and visible light between X-rays and infrared, breaking the sequential spectrum order.

Final answer: D