The correct answer is: D. G.B. Airy.
G.B. Airy was an English mathematician and physicist who is best known for his work on optics, astronomy, and tidal theory. He was the Astronomer Royal from 1835 to 1881, and he served as President of the Royal Society from 1871 to 1873.
Airy’s work on tidal theory was based on the assumption that the tides are caused by the gravitational pull of the Moon and the Sun. He developed a mathematical model that could predict the height and timing of the tides at any location on Earth. His work was a major advance in the understanding of tides, and it is still used today to predict the tides for navigation and other purposes.
The other options are incorrect. A. R. A. Harris was a British astronomer who worked on the problem of determining the longitude at sea. B. Isaac Newton was an English physicist and mathematician who is best known for his work on gravity and calculus. C. William Whewell was an English philosopher and historian of science who is best known for his work on the history of science and the philosophy of science.