For a single transducer to offer multiple frequency selections for scanning it must have?

• A. Large dynamic range
• B. Wide bandwidth
• C. Multiple rows of elements in the elevation plane
• D. Electronic steering capability

Answer: (B)

The ability to offer multiple frequency selections with a single transducer relies on having a wide bandwidth. Bandwidth is the range of frequencies the transducer can transmit and receive efficiently. When a transducer covers a broad frequency range, you can operate it at different center frequencies or use harmonic imaging while still maintaining sensitivity and image quality. A large dynamic range describes how much signal variation the system can handle, not which frequencies it can use. Multiple rows of elements in the elevation plane helps with elevational resolution or 3D imaging, not with accessing different frequencies. Electronic steering lets you switch the beam direction, not the frequencies. So, wide bandwidth is what enables multiple frequency selections.