Why might a practitioner select a low-frequency transducer for abdominal imaging and a high-frequency one for superficial structures, and what are typical examples?

• A. Abdominal imaging typically uses 2–5 MHz; superficial uses 7–15 MHz
• B. Abdominal uses 7–15 MHz; superficial uses 2–5 MHz
• C. Abdominal uses 1–2 MHz; superficial uses 20–40 MHz
• D. Abdominal uses 10–20 MHz; superficial uses 1–3 MHz

Answer: (A)