c) X-rays

The first American Nobel Prize in Physics was awarded for work in the field of X-rays. In 1901, Wilhelm Conrad Röntgen, a German physicist, was honored with the first Nobel Prize in Physics for his discovery of X-rays. This groundbreaking discovery revolutionized medical diagnostics and treatment, providing a non-invasive method to look inside the human body. The Nobel Prize in Physics for X-rays underscored the importance of this discovery and its wide-ranging applications in science, medicine, and industry.