Higher frequency sound beams scatter _____ than lower frequency beams.

• A. Less
• B. Not at all
• C. Much more
• D. Equal

Answer: (C)

Higher frequency beams scatter more because scattering strength rises with frequency, especially when the scatterers are small compared to the wavelength. In the Rayleigh regime, the scattering cross-section increases rapidly with frequency (roughly with the fourth power), so shortening the wavelength by using a higher frequency enhances how much energy is redirected in all directions, including back toward the transducer. This produces much more backscatter than with lower frequencies, even though higher frequencies also attenuate more quickly. So the statement that higher frequency beams scatter much more is the best fit. The idea that scattering would be less, not at all, or the same doesn’t align with the frequency dependence observed in ultrasound scattering.