Which scientist's work led to the idea that geological processes currently observed are the same as those that occurred in the past?

The correct answer is the scientist Charles Lyell. His work was fundamental in establishing the principle of uniformitarianism, which posits that the geological processes we observe today—such as erosion, sedimentation, and volcanic activity—have been consistent throughout Earth's history. This idea suggests that the same gradual processes that shape the Earth's surface currently have also shaped it in the past, providing a framework for understanding geological time and the development of the Earth's landscape.

Lyell's influential work, particularly his book "Principles of Geology," argued against the prevailing view of catastrophism, which suggested that Earth's features were formed primarily by sudden, short-lived events. By emphasizing the significance of ongoing processes and their cumulative effects over long periods, Lyell's contributions laid the groundwork for modern geology and changed how scientists perceive geological time and processes.

The other scientists mentioned have made significant contributions in their respective fields, but their work does not directly relate to the concept of uniformitarianism in geology as Lyell's does.