Ultrasound was first used by

Options

A. Olaf von Ram
B. Ian Donald
C. Hardy
D. Einthoven

Answer

**Step-by-Step Solution:**

1. **Understanding Ultrasound**: Ultrasound refers to sound waves that have a frequency higher than the upper limit of human hearing. These sound waves are used in various applications, including medical imaging.

2. **Clinical Use of Ultrasound**: The first clinical use of ultrasound technology occurred in 1956. This marked a significant advancement in medical imaging techniques.

3. **Key Contributors**: The first successful application of ultrasound in a clinical setting was conducted by A.N. Donald, a scientist, in collaboration with Tom Brock, an engineer. Together, they developed the first prototype system for ultrasound imaging.

4. **Conclusion**: Based on the historical context and the contributions of A.N. Donald and Tom Brock, the correct answer to the question "Ultrasound was first used by" is A.N. Donald.

**Final Answer**: A.N. Donald (along with Tom Brock) in 1956.

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