Ultrasound is used for diagnostic imaging and therapy. Which option best describes a therapeutic use?

• A. Increase range of motion
• B. Diagnostic viewing internal structures
• C. Visualize internal tissues
• D. Measure bone density

Answer: (B)

Therapeutic ultrasound aims to promote healing and improve function by delivering energy to soft tissues, which warms the tissue and can increase collagen extensibility and reduce joint stiffness. A common therapeutic outcome is increasing range of motion, since heated tissues become more pliable and less painful, allowing greater movement. The other options describe diagnostic tasks—viewing or visualizing internal structures or measuring bone density—rather than therapeutic effects of ultrasound.