The pioneer who first produced ultrasonic waves by whistling was; option [B] Galton. Sir Francis Galton, an English scientist and polymath, conducted experiments in 1883 where he used high-pitched whistles to generate and study ultrasonic frequencies. Galton’s research significantly contributed to the early understanding of ultrasonic waves and their applications, laying the groundwork for future developments in ultrasonic technology.

Galton’s experiments demonstrated that sound waves could exist beyond the range of human hearing, with frequencies exceeding 20,000 Hz. His work not only introduced the concept of ultrasonics to scientific inquiry but also opened avenues for exploring practical applications in fields such as medicine, industrial testing, and animal communication. Galton’s contributions to the field of acoustics and ultrasonics remain pivotal, showcasing his innovative approach and pioneering spirit in scientific exploration.